I'm not going into details as to what a witness does for the blockchain, but you can find them here, for example. Let me just say that without witnesses the Steem blockchain doesn't work. It's that important their role!
Taking a step back from the technical stuff which they are mostly in charge of, witnesses on the Steem blockchain are our "elected officials" if we were to draw a parallel to politics.
One significant distinction is you can have at any time a list of up to 30 upvoted witnesses, which in political terms would mean you can choose up to 30 candidates simultaneously to represent you.
Another major difference between the political arena and the witnesses system is there are no "term elections". Elections are continuously. You can upvote a witness or withdraw your support (by un-voting), at any time you choose to.
If you consider that a witness misrepresents you, un-vote him (or don't vote for him in the first place). If you find a witness which represents your interests and adds plenty of value to the blockchain / ecosystem, vote for him. Or you can have your own criteria, it's up to you.
@lux-wittness is a very new witness which has just applied to be approved.
Their team consists of two members, @sorin.cristescu and @pstaiano. You can see their application here, and I've just resteemed it earlier too.
Now, why do I campaign for this new witness?
I don't know Pablo, but I do Sorin, and he's a person with strong opinions, but who listens to the other party, and makes concessions when it is appropriate. He's also a continuous learner as well as willing to share from his experience.
They both have technical backgrounds, although from the description looks like Pablo will do most of the technical stuff, so I expect the witness node to run smoothly as they get more experienced with the software setup and that they will make hardware upgrades as they progress to top 20.
Sorin is the kind of guy who makes connections easily from what I've seen, and I won't put passed him the 2nd and even the 3rd point of their witness' "political" program.
Wouldn't direct conversion of Steem to fiat be awesome? Or the "pay with STEEM" dream?
Read their witness application, and if you are convinced, vote for their @lux-witness node!
I voted for @lux-witness a week or so ago, even before they managed to have a running witness node! :)
Aaa, important notice: I have no incentive for doing this (other than both I and Sorin being Romanian, I guess). I merely believe he can have a greater positive influence on the Steem blockchain, the more he progresses (and running a witness node is the next step).