All in all, though I'd like to believe the Barcelona will kick butt like that, it's a very poor source to cite because of all the variables.
For starters it's not SETI, it's BOINC, which includes many other projects all with varying ways of assigning credit.
Secondly, there is no way to know how much actual computing time is devoted to any given project be it 24/7 or 6 hours/day.
Third, this is an average of all the given CPUs in the project database regardless of their use time, project being worked, or OC state.
As an example, my 4400+ (running at ~2.6 GHz) does almost nothing but crunch SETI numbers 24/7 and averages just over 1200 credits/day. My Opty (2.7 GHz) is my main machine and is used for other programs and projects, some of which don't credit as much as SETI. It only averages ~1000 cr/day. The thing is, once you average ALL the 4400s or Opty 180s you get lower credits/day than mine because a good part of them aren't OC'ed and fewer still run BOINC as much as I do. The numbers listed have more to do with devotion to BOINC than to CPU performance ...