I think its hard to call this one. Normally I'd look at previous MGS results (and clearly the previous titles represent good data points) but I think the following effects are hard to call right now:
a) general growth of videogames market. The market is much bigger than when last PS2 MGS game came out and looking at sales of AC (which I think is a reasonable comparison game) vs its 'light' gameplay I can easily see MGS 4 outselling previous iterations assuming reviews/hype are good
b) GT5:P sales indicate to me that PS3 owners (or those considering the console) will respond strongly to proven PS brand franchises and MGS 4 to me has long been positioned as the 'must have' PS3 exclusive
c) It's exclusive and previews indicate it does use PS3 HW well and deliver a good reason to play games on 1080p TVs
d) Will GTA IV impact this game? Could it become the PS3 'must have' title even though it's multi-platform and will gamers lean to it vs MGS?
Depending upon how you judge the above I can see MGS 4 selling the same as MGS 3 or selling above the others. While a) b) and c) I think are all looking good for the game, I wonder if d) will drive HW sales for PS3 that reduce impact of MGS - i.e. will people buy a PS3 for GTA IV knowing MGS is coming vs buy a PS3 when MGS hits?
Try to be reasonable... its easier than you think...
