Regardless of what alot of people think, the PS3 has some sales numbers as being bought just to play Bluray. It's still the best option as a Blu ray player. At christmas I think Bluray players will be alot cheaper than the PS3 and I think when this happens it will hurt PS3 sales a little.
The PS3 will still sell well over christmas but into next year when the Blu ray adopters can pick up a stand alone player for under £200 the ones who care nothing for gaming will do that option. Blu ray stand alone prices I think have helped PS3 to sell better.
Time will tell. However I think in 2-3 years when the gen is over and the next begins Sony and M$ will be mighty close.