TFT's for me. It was a huge improvement to upgrade my (old and cheap CRT, admittedly) to even a budget TFT (Samsung SyncMaster 710T).

The image is A LOT sharper (I have DVI), making text much much easier to read. It also has a handy pivot function, so when working on some writing, I can rotate the screen 90 degrees and MS Word will automatically "tilt" the buttons and everything else, so it's like having the dimensions of a sheet of paper to work on. It's also very handy for reading pdf documents, as it will display one page at a time without having to scroll at all.

I also noticed I can work for much longer periods of time without straining my eyes as much, as the image doesn't flicker at all (constant backlight instead of flashing 50-60 times per second as on a CRT).

It all really depends on your needs, some people will benefit from a CRT and some from a TFT. This thread has been very informative though IMO, some good points for either side.