Some sony fans to be dissapointed with FFXIII sales and its effect on ps3?

[Ail]

I believe FF XIII will do less than the previous iterations in the serie in Japan but has the potential to do more in Others. Of course having a WW release as opposed to a Japan only release first would help.

For hardware it all depends your expectation.
When all is said and done MGS4 will probably have helped sell 100k extra consoles or so in Japan, doesn't seem like much except it's 5% of PS3 Japan sales.

I think you can reasonnably expect FFXIII to sell 200-300k extra PS3 or so in Japan, which will be around 7-10% of the install base at the time it comes out..