Don't rush out and buy a new dvd player, for heavens' sake!
It is similar the the betamax versus vhs war of long ago (still have nightmares about it - guess what I bought?)
Although blu-ray may be winning the battle, the war isn't over yet.
Thankfully you can buy players that play both blu-ray and hd but they will get much much cheaper over the coming months. Most of these will play your old dvds too.
Currently dvd films in either hd or blu-ray are very expensive compared to standard dvd, and unless you have a hd tv, you won't get the benefit.