I was more concerned about Ray Allen getting a sizable offer from another team prior to the summer. Since then, half the teams that figured to have cap space (18 teams down to 9) have traded away their cap flexibility (particularly contenders like the Cavs, Mavs and Spurs). Resulting in less competition in the market place and most of those teams should end up fighting it out for the superior talents.
There's four teams with $12+ million in cap space -- NJ, Miami, NY and Chicago (if Salmons opts out) -- I don't think any of those teams will be a threat to sign Ray Allen. They're all young teams looking to add an All-Star to MVP caliber player to build around.
That leaves five other teams -- Oklahoma, Minnesota, Houston, Clippers and Sacramento -- I can't see Sacramento, Minny or Oklahoma making a run at Ray Allen due to age/youth of roster + present SG. I also think it's highly unlikely that the Clippers try to sign Ray Allen but still somewhat possible.
Houston is the only team with cap space that I can see having interest in giving Ray Allen a substantial contract. And they are very likely to use all their cap space to keep their own players (Hayes, Landry, Dorsey - team options/non guaranteed) + re-signing their own talent (Scola, Lowry). Once they've done that they'll only be left with their MLE.
To conclude, I don't see any threats out there in free agency. I don't think any of the teams who have cap space are going to be interested in a player like Ray Allen (except maybe Clippers and that's a long shot). Consequently, I think Ray Allen is going to be reduced to MLE offers in free agency. The market place just isn't there for him.
Which in turn means the Celtics should be able to sign Ray Allen on a cheaper contract. Just above the MLE (say $7 million per annum) but not nearing the $9-10 million mark.