The latest edition of Bimmer magazine has a roadtest of an X3 3.0si 6MT. They had some very favorable things to say about it, including that they prefer it to the E91 328ix Sports Wagon in regards to overall handling and performance.

BTW - A X3 3.5si is rumored for a 2007 introduction, complete with the 3.0L biturbo engine currently found in the 335i. That might be worth the wait.