I was thinking of going the humble route and submitting my own avatar for the logo. bdm860's Celtics Strong, has a nice ring to it.
Not hating on those who submitted, no doubt more talented than me, but some ones I don't like:
#17 looks too much like the old Sonics logo for my taste.
#7 looks like a biohazard symbol to me. #6 is kinda weird too, biohazard meets Olympics.
That hand doesn't fit in #11
For what I do like:
I like 20, but I don't think it works well as a main logo.
Something about #12, I don't think it would work well as this sites logo, but it looks really cool. Like a patch someone would sew on their jacket in a different era.
To me, #3 and #19 are the front runners. They convey in a simple manner what I think a logo should look like without being too busy, and hit the color schemes I'm used to.
One thing I remember Jeff saying at the old site though, something about having to get the logo cleared by the actual Celtics. That's why CelticsBlog had a 4-leaf clover instead of the regular Shamrock. A lot of these are too close to the actual Shamrock, I think the C's would look to protect their IP.