Teams know that if they throw out an MLE deal, the Bucks will match and Sessions will belong to the Bucks for the next 4-5 years. If Sessions does not sign an extension and simply accepts the qualifying offer, he'll become a UFA next year in the season of 2010 when a ton of teams will have cap space. Since the other 29 teams know they CAN'T get him this year (Bucks would match) their best bet is to sit and wait and hope he takes a one year deal...and then run at him next year.
With that in mind, if the Bucks can't him to sign an extension, they would probably be open to trading him during the season because they'd rather do that (trade his rights) than loose him for nothing. They also have Jennings to run the show soon. They'd probably accept a trade back...but for what? Maybe they like Freeland and could use a big to go with Amir Johnson and Bogut (and Joe Alexander who is their 3/4 tweener like Outlaw).
The Bucks seem to go through a new PG ever couple years: Ford -> Williams -> Sessions -> Jennings
So I think maybe we're standing pat hoping that this scenario plays out, so that we can trade for him using our cap space in an extension sign and trade. Just a thought!
If it comes down to it...do you trade Rudy for Sessions straight up? Milwaukee is in sort of a youth movement of their own and probably would look to unload Redd soon. If they had Rudy at the SG they'd have a talented piece that would justify them moving Redd and keeping a young and talented (and cheap, which is important) core.