Dennis asks, "Should more people run a full node...
in light of the recent contentious hard fork and user-activated soft fork?"
You should run your own node so you can independently validate transactions.
If you are not running a node, validating [transactions based on] the rules, you are not part of consensus.
You are not participating in consensus.
If you need to ask someone else [whether] a transaction [has confirmed],
[such as by] typing you address into a block explorer in your browser,
you are delegating your ability to independently validate if that transaction confirmed...
according to the consensus rules.
[By] asking someone else, you're delegating that [responsibility] and that is centralization.
Who knows what consensus rules they are running to decide that?
[Could] they telling you that it was [confirmed] on a fork [you don't follow]? The wrong fork?
You should run a full node to be able to answer those questions yourself.
The reality is, most people [don't know how to do] that technically. It is not easy.
But more people can [than currently are].
It is much better if you can run a full node that operates on an independently controlled internet connection,
not running on a virtual private server, through Amazon Web Services, etc.
If you have an internet connection at your home and the desire to use this technology [properly],
you can [even] run a node on [a computer that is not very powerful]. It doesn't take much to run a node.
Any desktop will do. You can limit the amount of disk space and bandwidth you use...
[changing the] appropriate parameters and configuration options in the Bitcoin Core software.
You can [use] different [but compatible Bitcoin client software], if you want.
You can run a node even with a tiny bit of bandwidth [or disk space] by not keeping a full copy of the blockchain,
but instead pruning it, [which] will [still] give you the ability to validate.
It will not give [other nodes on the] network the benefit of your bandwidth and storage to help bootstrap,
or support lightweight clients and things like that.
If you have a connection that is not capped or is capped at a reasonable [amount],
[such as] 200 - 300 gigabytes per month which is often the case with cable and broadband providers,
then you can offer a service for the network [by] keeping a full copy of the blockchain.
This will help new nodes bootstrap, help lightweight clients run,
and improve the resilience, robustness, and security of the entire network.
If you can do it, do it! It is a great experience. You will learn a lot about different [aspects of the] technology.
You learn about how to compile and run software.
Even better, if you really want to get your hands into a nice meaty project,
check out the Blockstream satellite program.
For about $150, you can buy a 40-centimeter Ku-band satellite dish, basically the same dish you see...
on houses [with] DirectTV or one of those [television] services.
You can buy one of these satellite dishes, put the right receiver on it,
and connect it to a USB software-defined radio dongle (which you can buy as part of a kit).
[It can be a] nice weekend project.
[Then] get up on your roof, [position the] satellite dish [so that it is] pointed in the right direction,
connect it to a desktop, plug in the USB software-defined radio, and now you have a node...
that is receiving blocks and transactions from a satellite, to compare against [what you] receive over the internet.
Perhaps [you could] also serve internet clients from your satellite feed.
That massively increases the resilience of the network.
So yes, you can do a lot to help increase the resilience of the [Bitcoin] network.
"Why is a satellite connection so valuable?" This is a quick follow-up to the previous [question].
A satellite connection is so valuable because, even with internet outages [or censorship] in a particular region,
if you have nodes connected via satellite, they will remain connected.
The satellite replays information from the last twenty-four hours, so even if you [lose internet access]...
for half a day, you can catch up with your satellite connection.
If you lose internet for days or even weeks, you can remain synchronized with the Bitcoin blockchain.
over the satellite connection.
This means that the [Bitcoin] system is [more] resilient to shutdowns,
even deliberate shutdowns [with] port blocking and other censorship activities on the internet.
When you regain your internet connection, perhaps over Tor, a VPN, or a different port,
you can then [broadcast] those blocks and transactions to your neighbors who don't have a satellite dish.
You are not only resilient to censorship [yourself], but you undermine the censorship of others...
by giving them blocks and transactions through various types of other networks, like Tor and VPNs.
"What would be the requirements for someone to host a Lightning Network payment channel?"
"Will this proof-of-stake model make the rich richer?"
I think the requirements are fairly lightweight, actually.
There is an implementation of the Lightning Network daemon that uses a light client called Neutrino,
[where] you don't need to run a node that stores the full Bitcoin blockchain.
You don't even need to run a fully validating node;
instead, you run this lightweight node that validates the block headers and transactions.
It is a much lighter weight node [rather] than a full node, [so there are trade-offs in terms of security].
In conjunction with a Lightning Network node, that can run on a smartphone.
One of the [Lightning wallet developers] named Jack Mallers recently demonstrated a main-net transaction,
running via a Lightning node on an Android smartphone, managing its own payment channels and even routing.
You [will be able to] run that [too], in the form of a wallet that runs a Lightning node,
can open payment channels to [other] Lightning nodes, and route payments between them.
It can either use a connection to a fully validating node [with a] Bitcoin Core client,
running somewhere on a server that you control, or run as a lightweight node like Neutrino.
The requirements [can be] pretty low. You can run a Lightning payment channel and route payments...
without a very big computer; arguably with less resources than you need to run a full Bitcoin node.
"Will this proof-of-stake model make the rich richer?"
[This is based on] the idea that if you have [many] payment channels funded with large amounts of bitcoin,
then you can collect lots of routing fees, which makes you richer and allows you to run even more channels.
This has been one of the persistent fears [about Lightning, but] I think...
there is pressure in the opposite direction.
You can route small payments with just a few payment channels that are not very big in terms of funding.
You could [use maybe] a tenth of a bitcoin, run fifteen channels to a bunch of nodes,
and start collecting some small fees [to] increase your holdings.
You may think, 'why not run five hundred channels and fund them fifteen bitcoin?'
Well, by putting fifteen bitcoin in a system [that uses a hot wallet to] control keys,
the risk of losing that is much higher.
There is this opposite pressure against centralization.
As you [fund channels with larger amounts], you are increasing the risk of theft,
for the same reason that exchanges [probably have a higher risk of theft] than a wallet on your smartphone.
The exchange is trying to protect millions of dollars worth of assets under the control of just a few keys,
whereas with you running a single wallet [or multiple wallets, that is] a lot harder to hack.