No need for a blu-ray for me. That is until I saw the Star Wars box set released on blu-ray. That got me wondering. But in all likelihood, I'll probably never get one since I don't feel like rebuying all my DVD's again in blu-ray format. If I get a PS3? That's another issue.
Why would you have to re-buy all your DVDs? The BluRay player will play your existing DVDs just fine, and in most cases, will upscale them and make them look better than a standard DVD player. No reason for that to be your deciding factor.