Not necessarily the titles above but, Xbox Live Arcade titles coud be changing to a maximum of 800 achievement points according to a source informing Xbox 360 Achievements.org. Microsoft plan to change the policy rules to make Arcade games more attractive to Gamerscore hunters...

The 800 maximum points will - of course - not be available at release of the title, but over the lifespan including DLC. However the base 200 points plans to be changed to 400 which can only be a good thing for developers and players. More room for developers to add story based achievements and more incentive for us Gamerscore hunters to look for Arcade titles. Take note that this most likely will give Microsoft justification to increase the price of a title. You seriously didn't think they give us more without extra buck?

Source : http://www.xbox360achievements.org/news-2563-XBLA-Achievement-Policy-Change-Coming-Soon.html

technically, the biggest complain from devs are the size restriction of 2gb for xbla.

good for those GS whores

no use for me, just wanna complete the game then move to next one

And whatever they're doing caused some ppl's gamerscore to reset to 0. My heart stopped for a second when I noticed that.