One of the major questions when deciding to file is to see if you are above or below median income. Evey year, the median income numbers for each state are revised. Effective 5/2012 from the Office of the United States Trustee:

New amounts:
1 Earner: $52,712
2 Person family: $64,403
3 Person family: $78,296
4 Person family: $85,337
+ $7,500 for each additional family member

These numbers are up from last year, about $2,000 on average. If you are close to the median income numbers, you may want to wait until May to file.