(I don't know what was said on page two of this thread because work has decided that that page is worthy of being blocked.)
It depends on the context. I don't use it for myself, because I don't particularly associate with being trans, and it's more often associated with women, so I don't feel like it's really my word to reclaim. Very, very, very occasionally I'll say it tongue in cheek when referring to myself and I'm with people that I know won't take offense from it, or take it the wrong way, but that's it.
When other people use it I have to remind myself that it's probably simply because they're uneducated on the offensiveness of the word, similar to the way that they often say "->-bleeped-<-" when meaning "transsexual", or "hermaphrodite" instead of "intersex", because of being uneducated. It's not something which is commonly come across for most people, and trans people are still seen as something other and rare in a lot of cases which doesn't help. The majority of people don't know, or don't know that they know someone who's trans, so it's hard for them to get a grasp of it being something which happens in reality. If I know that it's highly likely to just be a lack of education causing them to carelessly use the word then I don't mind it so much, but I do always get a twinge of discomfort at the fact that they could be using it in a derogatory way.