The Spurs have multiple expiring contracts and draft picks, so the ability to make trades is there. I'm sure they'll continue to look for a deal that makes sense.
If Pop is basing these comments off anything, it'd be the realization that Maggette isn't coming to town. Perhaps the Clippers said the deal involving Barry is officially off the table. If Pop isn't saying these comments just to say them, that's a plausible explanation for what caused the change of heart.
If the Maggette deal is dead (as I expect it now is), the chances of an impact trade are pretty low. At most, I can imagine something like Williams, Beno and a pick for Atkins.