Sub-portals
Create sub-portals for popular languages and platforms, similar to facebook.stackoverflow.com. This would be akin to a View in a database where you would see only a subset of the site, whether browsing, searching, reviewing, handling flags, etc. For example, a Java portal could include not just java, but also jsf, spring,playframework, etc.
Allowing people to focus on a specific area of interest divides the problem into more manageable chunks, and cleaning up their particular slice feels like a more achievable goal, just as Facebook.SO's 16000 unanswered questions seems a lot less daunting than the 700,000 on the full site.
Likewise for reviewing, seeing only a slice of the 40.5k low quality posts and 58.7k close votes would make it seem a lot less futile.