First of all, it is my understanding that all clients will detect certain easy-to-spot misbehaving by delegates -- automatically, and downvote them accordingly. Is the opposite also true? Will longstanding well-behaving delegates be automatically upvoted?
There is no automatic voting.
What constellation of conditions is necessary for a delegate to reach the top 101? Does that list tend to stay the same, or it's always rotating, possibly enforced by the system?
You need people with stake (read BTS) to vote for you. Top 101 by amount of stake voted are delegates.
Is there some 'delegate explorer' website out there?
bitsharesblocks.com (thanks to svk)
Lastly, pertaining payouts, it is my understanding that delegates get paid in bitshares, correct?
How many bitshares will that be -- does it depend exclusively on the burn rate, or also something else?
Depends on the payrate. It is visible in bitsharesblocks.com
I read somewhere that at (that) the moment, a delegate is expected to get about $2500 equivalent in BTS, presumably for a month of service. Is this more or less right?
Depends on the exchange rate of BTS. Numbers vary.
If so, as an extremely well versed systems administrator who's fully comfortable with securing unix systems to high grade, what prevents me from setting up 100 delegates (I realize many/most would not make it to the top 101), wait for them to become stable and accepted in the network, and sit back & watch the money coming?
Delegates are voted in by stakeholders (owners of BTS).