If you go to the Adobe premier pro website and click system requirements, you will see the computer specifications.
With what you said about HDV and not wanting to upgrade, as other have said HDV is young and you will see advances made which will give yo a better quality and other improvments.
Camera CCD's though currently mainly Cmos in alot of cameras, is going to see a new SCCD3 (model not 3X ccd) which will give alot better quality than is currently available. HD will become alot bigger than its current 1080 line and will proberly move to more like 2500 lines.
With that said, it could be a few years away and you could always be chasing the next best thing.
Blue ray is available, but not for domestic DVD players so its a bit of a waste, you will be looking at dual layer to get high quality on to disc, I am not versed with the up and comming disc burning and DVD production software, so you will need to look into that.
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