I previously bought PE4 as it stated that it had compatability with the JVC format that my camcorder used at the time. Unfortunately the compatability was very poor, so much so that i gave up on it in the end.
My camcorder has now died and i am looking at getting a new one and also upgrading to PE8. Are there any manufacturers/makes/file formats to be avoided for complete non-compatability or even just poor compatability?
Tape-based formats are the best for interfacing with the program -- either miniDV or HDV. And, yes, JVC are notoriously iffy. But with most major brands -- especially Sony, Panasonic and Canon -- you should have no problems. Fortunately, miniDVs are very cheap now (under $200)! And, among HDV, the Canon HV series are some of best under $1000 camcorders you can find.
Among the hard drive based formats, I'd only recommend AVCHD, the format used for hi-def hard drive video. The downside is that this format takes massive computer power to work with, and most people who are successfully using it are running a quad core processor with 4 gigs of RAM.
Finally, if you plan to edit your videos, stay away from non-traditional video formats. That would include pocket hi-def and "webbie" cameras, like the Flip, and video from still cameras.
For a Firewire DV Camera - look at Panasonic PV-GS320 or GS500 (Note that I have not used either, but they have good reviews)