The window to respond is open for a few more days, but as of 9/15/2013 from the CAL IAH CP:

Recalls and hiring
As of midnight on Sunday, Sept. 15, 205 pilots had responded to the recall notices. 23 accepted recall, 87 accepted recall but are on military leave and 95 chose to bypass. The remaining furloughed pilots have until Sept. 24 to respond. Those accepting will be placed into classes between Oct. and Dec.and will have some ability to choose. United will continue to hire off the street during this period for classes where there are not a sufficent number of furloughed pilots who have acepted the offer of recall. Between recalls and new hire pilots, we plan on bringing on about 60 pilots a month through the end of the year and possibly going to 100 for the first six months of 2014.