I test drove the US Spec'd Luxury model with the 3.2L, auto, and I have to say, I was impressed. From what I've heard, it's a bored/stroked version of the 2.7L. The most significant difference is that the engine has alot more low end torque than the 2.7/2.5 which tended to be flat until you hit 4000 rpm, then it would pull like crazy. The new engine has a much more consistent power band throughout the rpm range, which is considerably nicer.
I'm going to be purchasing the new 3.2L in a few months, but figured I'd report my test drive. On a side note, it also stops better than the previous disc/drum version.
-Zukisidekick