The numbers correllate well with the OP's theory.
We are collecting the list of 3rd party exclusives for each platform. The work is not done yet but we can start seeing some significant trends. Follow the link to get the details.
http://www.vgchartz.com/forum/thread.php?id=50914&page=1
So far we have counted:
- X360 3rd party exclusives: 58
- PS3 3rd party exclusives: 10
These are the exclusives known to be(or have been) released from October and throughout 2009.
58:10 is a pretty striking difference between the platforms. It essentially means that the 360 will get 5 exclusives every month. Pretty significant. Some of these exclusives are pretty big titles.
Economically, 3rd parties should have all released their titles as multiplats. In theory. The reality shows that a significant number of them are skipping the PS3 on their own accord. The testimony in the OP may have a lot to do with the reason for the decision to give up on the significant market of the PS3 users.
Late edit - the number of 360 exclusives in the list was reduced to 58 (from 68 in the original version of this post) due to errors in the list.
Prediction made on 11/1/2008:
Q4 2008: 27M xbox LTD, 20M PS3 LTD . 2009 sales: 11M xbox, 9M PS3







