There is a temp CFW for OFW 6.61 called LME. Here's a link to the download: http://www.mediafire.com/download/y0yzmy1iu3av541/release_661lme2.3.zip
Than update to 6.61 via the XMB by going to the Settings section in the XMB and hit Software Update. Than hit accept and let it update.
Once you...