You should be okay working with the imported Premiere Project. But don't expect to import the completed AE project back into Premiere: render it out, and don't use HDV for the codec; it's very lossy. Depending on your AE version & system setup, you may have to turn off multiprocessing in AE Preferences.
And NEVER use Open GL to accelerate your rendering: it causes so many problems that Adobe removed the option to use it in the latest version of AE.
I'm on a pc Windows 7. What codec should I use? If the original is HDV, what are my choices?
I'm in Vegas, going to NAB. What should I look for to capture from HDV camera? If it's lossy, what can be done after the fact? I won't be upgrading for some time. Which cameras/formats seem to have the best success these days? (from editing/picture standpoint)
Is CS6 a worthy upgrade from 5.5?
I'm a Quicktime guy, even on my 24 GB, dual-quad-core Windows box at home. I like QT's PNG codec. If you're not a fan of huge file sizes, Avid offers its DNxHD QT codec for both Windows and Mac, it's free and it's reputed to have extremely good image quality: the quality's right there with Apple's ProRes 422, which is NOT universally available. I'm on Macs at work and Windows at home, but I'm yet to convince the techs to augment (gasp!) the codec selection in our edit suites. So I don't have personal experience with DNxHD. But one of the guys mentioned below sure talks it up!
If you're at NAB right now, just go to the Adobe booth and discuss your needs. Look at CS6. Get your answers from the Horse's Mouth.
Don't think you'll get a straight answer from Adobe? Try to find a guy named Walter Soyka and grill him. Very knowledgeable & authoritative. So is another gent, Walter Biscardi. You may find them at the Creative COW booth, or they may be busy running demos for other products. These guys are g-o-o-d, GOOD!
Premiere Pro CS6 is a LOT better than CS5, I'm told.