Why a significant talent boosting trade is highly unlikely, even without Jefferson.
The Spurs are over the salary cap or they don't have a TPE, so they cannot absorb players without giving back close to equal salary.
The Spurs have big contracts such as Tim Duncan, Manu Ginobili. We are not trading Duncan, and for a rebuilding team, they wouldn't take an old Manu, same goes for Duncan because they would not fit their plans to get a player of Chris Paul caliber (I said caliber, not Paul, he was an example).
Our most valuable trade chip is Tony Parker, who is an expiring contract. As far as that goes, teams are afraid Parker would not sign an extension and jump ship next off-season. No team will offer valuable assets for him.
Young talent. The Spurs have George Hill, DeJuan Blair and James Anderson. I doubt they will trade Splitter. Unless packaged with bigger contracts, the Spurs would not be able to get significant talent back for them. And we only have Duncan, Manu and Parker. It is really hard to trade them for equal or over value.
Assuming we didn't re-sign Matt Bonner, the Spurs have the option of a S&T of Bonner and Mason, but who the would do a S&T for those fellas?
Another valuable trading chip is Antonio McDyess who has a partially guaranteed contract after 2011, so his value is highest then. Why trade him now?
Un-guaranteed contracts are Temple, Hairston, Gee. Again, like Anderson, Hill and Blair, none will be able to be packaged with a big contract to get a significant top 8 NBA player to get the Spurs back in the mix.
Draft rights: Bunch of players like De Colo, Ryan Richards. These guys won't fetch significant talent either.
Draft picks: Late 1st round picks, they are not valuable at all.
Conclusion: Sure it is good the Spurs have good players on their team, but none of them are really viable, or players who can be dealed for way better significant players. They have quite little to work with in terms of current players for trades. The Spurs would essentially have to gut the whole roster just to get a big piece to the puzzle, which clearly is not the Spurs' style nor is it plausible.
Ya, I think that is all from me for now. I will get back to this some other time.