2011 taxes were due in April, but so long as all the money is in (possibly in estimated tax payments with an extension form), most people and organizations don't need to submit the full paperwork until six months later. Rather famously right now, Mitt Romney hasn't. (He's promised to make this year's and last year's returns public, but this year's isn't done yet.) So, it's quite possible that a bare-bones charity is also taking advantage of the extension.

(You won't get any refund until you file the full return, you'll get hit with penalties if your estimated payments undershot the actual tax due by very much, and shorter deadlines may apply in particular cases, like people filing from overseas. But most folks can get the full six months.)