I'm not as impressed with the fact that the PS3 passed the 8m mark as I am at how well it sold in Others this past week. It sold > 100k over 360, which is a sizable percentage considering the numbers.
I have to admit that I was skeptical about the PS3's survival even by late fall, but I believe it's reaching a critical mass that will allow it to do well long term, even if it doesn't dominate (which I think is unlikely considering how few exclusives the PS3 has compared to what the PS2 had, and the Wii seems to have captured the hearts of the casual gamers). My guess is the price cuts and improving games library is largely the cause. If PS3 does well in NA this week (I think the Japanese market just doesn't provide enough sales, percentage wise, to really make or break a console anymore), and the software library keeps growing at a good pace (avoiding chronic delays for the big titles), then I would say that PS3 is here for the long haul.
Personally I think this is a great thing... a 3 horse race is usually more effective in terms of keeping companies competitive than a 2 horse race. Prices should keep falling on the 360 over the next 12-18 months, and we might even see a Wii price drop next year if PS3 sales keep up. Yes, it's Christmas, etc., but if I was a games publisher I would be salivating at the sales prospects on that platform, even if the PS3 sales drop dramatically during the 1st and 2nd quarters... good installed base usually means solid software sales.
Hats off to Sony. They didn't zoom out of the gate, but they seem to be doing well now. Yeah, I doubt PS3 will ever reach PS2 levels considering the lack of BC on some of their boxes and the very high initial price, but I don't think the platform is in danger of going away.
And before someone calls me a Sony fanboy, I own a Wii and a 360 and have no intention of buying a PS3. 
