We need an actual figure to determine success of sales, or if you're saying about reaching expectations, we need figures from Sony about what they were expecting.
Zassk has summed it up pretty well.
But again, here are a few options:
- MS has probably sold more units with a lesser number of total exclusive games
- Sony's exclusives seem to have been a lot more expensive
- General consensus is that Sony's exclusive lineup is better, although I haven't really checked every game's aggregate scores
Because of all this, one would expect to have Sony with a lot of games above 4-5 million units, but they only have MGS4 at ~4.4 million. Whereas MS has Forza, two Gears, two Halos - almost all of these released to a much smaller user base; and their combined sales are ~30 million units, more then the top 10 PS3 games.
So the general performance of MS exclusives is far better even though they are considered to be inferior.
That is why I say that except for MGS4, no Sony exclusive has sold as well as it's been expected; KZ2 in particular considering the buzz and the budget (probably the most expensive exclusive until GT5).
Other titles like U2 selling 2.5 million units (quote from deepbrown from other thread) strikes me as good sales. If we can't count 10% of userbase as good, there's no hope for the industry!
In the case of UC2, it's arguably one of the best games of the year, certainly in terms of review scores and graphics. I'd also say that it has very wide appeal - it's easy to get into, it looks wonderful, and so on.
So it would be reasonable to expect that it can outdo any other PS3 exclusive, including MGS4, but it seems the game isn't really on track to do so. We've already had a lot of discussion about why it isn't making the killing that it deserves... so it's definitely not performing as well as expected. Hopefully in time it can at least outdo the first Uncharted.