I realize this has been mentioned before, but I narrowed down a bit what makes the find/replace slow, so I thought I'd mention it.
I was doing a find/replace in a single file, using a regex; the file was about 950KB, and there were about 3500 matches. The replace took many minutes (enough that I got coffee, came back, it still wasn't done, so I killed it). The same behavior occurred when doing it as a regular replace (e.g. not a regex).
What seems to cause the pain is, at least in this case, the file was all a single line. When I broke the file up into 30 lines or so, the replace happened in less than a minute. Still seems way too slow, but it was dramatically faster.
I'm hoping this can be fixed...I get these files from our server back-end for failed processes, and I need to massage them into something I can use for debugging by doing a find/replace.
update: this was on build 2181.