Hi,
A few days ago I submitted to Anthony Forbes a 597-digit 6-tuplet and had it verified as a new world record:
http://anthony.d.forbes.googlepages.com/ktuplets.htmThis number is only a few digits above the previous record, and it should be quite possible for the superblock project to beat it!
The program used was based on the b14 version of dga's xptminer (which was the latest version I was able to compile using Windows and Visual Studio) and ran on 11 cores for about a month before it suddenly surprised me with a find. I'll give some further details later.
Regards,
Vidar