Personally I am looking forward to the 661 and if I don't buy a 660 in the coming year then I will probably buy the 661, with that being said there are few being tested somewhere is the US or Germany. Stihl seems to be very tight lipped about this saw which is good at keeping us at the edge of our seats lol. The big question is when when will it be released? I can not tell you but my theory is that if u look at the 461 "test" pictures that were posted here 1-2 years ago it took about a year after those were posted for that saw to be released in Germany, I am thinking it may be another 8 months to 1 yr and a half before we see the 661.