I tend to find written sex the hottest when I'm writing, actually. I think because I really prefer visual porn? I don't read fic for the porniness because it doesn't really do anything for me and part of that is that I don't visualise when reading and images are what I find arousing rather than words. But when I'm writing, I tend to visualise more (still not very well, certainly not the equivalent of a movie in my head or even still pictures, but I can focus somewhat better than what I get when reading) so I am actually "seeing" it more.

As for what I want to read, well, as I said, I tend to write the sort of thing I'd like to read and for the most part it doesn't tend to line up well with what the rest of fandom is writing.