It'll be pretty damn close. With the extra boost Sony is getting from its price cut (especially in EMEAA and Japan), I think a lot of multi-plat games are going to be closer this holiday.
For MW3, I think the lead PS3 usually has for it in EMEAA and Japan could be even larger this year, which will help combat the gap in Americas. So I think the gap at the end of the year will be more like 1.5 million, instead of the normal 2 million or so.
For Skyrim, the same will hold true. The gap between the last Elder Scrolls was ~1.1 million. Of course, that was early in this gen and it launched months later on the PS3. This time that it not the case. I see Skyrim selling more in EMEAA on the PS3 and there being a larger gap in favor of the PS3 in Japan. Skyrim will probably be a tie, but may end up in favor of the PS3 thanks to those 2 regions.
For AC:Revelations, I see it being a tie, again thanks to the boost in EMEAA and Japan. If it does go in favor of the 360, it will only be by ~100K or so. So nothing that will really tip the scales.
Of course, we already know what's going to happen with FF13-2. It will pretty much be like a PS3 exclusive in Japan. So yea, a PS3 lead of 1-1.5 million lead could be right.
Some are saying Kinect SW will push the 360 ahead, however, I'm not seeing it. Sure Kinect SW, mainly Kinect Adventures, will get a boost, but it's not like Kinect games are flying off the shelves. Look at Dance Central 2, for example. In 2 weeks, the first one sold over 230K. Dance Central 2 has only pushed ~160K. It's total for Week 2 is just over 42K, a number the original hadn't dropped to in its first 10 weeks. Then you have Kinect Sports 2. In it's first 2 weeks it sold ~164K, while the original pulled in ~458K. It's total for the 2nd week was just over 60K, again, a number the original hadn't dropped to in its first 10 weeks. And these aren't scrapping the bottom of the barrel for comparisons, these were some of the top selling Kinect games. So, Kinect may do alright in Americas, but everywhere else it's almost nonexistent.
Also, isn't PS3 SW undertracked here? Not unless the PS3 had ~75-80 million (I think that's the gap we had between shipped in Sept) games on store shelves. Seems a bit much to me.
