I'm rather new to this Q&A, but webapp-rec is by far and large the most common tag here.
On Gaming, list-of-X moderation has been very strict, which has brought tough discussion of what list questions would be acceptable. It also has not stopped game-rec questions from trickling in, however.
My stance on this is that if the question is specific enough that only a few, non commonly known web apps cover your specific needs, recommendation questions can be good: they need expert answers that generic lists of software on Wikipedia cannot give.
On the other hand, if the question is sufficiently broad, people will stop voting for the answers and start voting for the apps, turning the question into a popularity contest that should not generate any rep, should it be allowed to pollute Google results at all. (Yes, I know that by linking to it I increase its ranking. Sigh.)
This is why I think that, e.g., What blogging engine supports markdown? is a good question, while "What blogging engine supports RSS?" should be mercilessly answered, "All of them". (And then closed, locked, caged and drowned.)
I haven't lurked enough to make good examples here. Sorry.