This was revealed in a "We've hit 50,000 followers, which means it's time for an announcement! Coming Fall: a new way to earn Rewards based on your Achievements!"by the Xbox Live Rewards Twitter feed, pronouncing,
What does this mean? No official details have been revealed, but it sounds like being a "Gamerscore whore" will finally be reciprocated by Microsoft.
Microsoft: Achievement-based rewards coming this Fall
19 June 2012 | By JonahFalcon