I have only one prediction about PS3 is that it will sell more in 2009 then in 2008. It could be "marginally" more due to no or late drop in price, or a big increase due to increase in price but more or less, the sales will increase. It might still be lower than xbox 360 though.
Sony is not playing for the first place (in Short-Run) since they have seen that it would be too costly for them now; so they are simply trying to minimize their losses while increasing the userbase. They are not worried about losing the third party support because they wont. They will probably not be the leading platform for good or for a long while, so machine will look on par or inferior to xbox 360 on third party games maybe, but there are always the first party titles that will show the real difference (which is in my opinion is hardly important as Xbox was much stronger than PS2).
If the price drops in 2009 or 2010, the 2010 sales will be even bigger than 2009. So the PS3 sales projection could be partially true (although highly overstated). Xbox 360 sales are highly underrrated on the other hand, and it also doesnt make much sense to imagine that PS3 will pass or get so close to the wii anytime soon!
In Short, even though I am almost sure that PS3 sales will improve in 2009 and even more in 2010, they will lower than wii, also could still be lower than xbox 360. Even if ps3 could surpass xbox 360 in 2009 and 2010 in weekly sales, the total sales will not surpass xbox 360 before 2010 (probably mid-2010 as earliest).
Playstation 5 vs XBox Series Market Share Estimates
Regional Analysis (only MS and Sony Consoles)
Europe => XB1 : 23-24 % vs PS4 : 76-77%
N. America => XB1 : 49-52% vs PS4 : 48-51%
Global => XB1 : 32-34% vs PS4 : 66-68%