I considered buying a VW Golf Diesel, but the maintenance would have too big of a hassle and it's not a Honda. If Honda can bring the Diesel here, I'd buy one tomorrow. Unfortunately, cars are going to be restricted on diesel emission in 2007, which is going to really hurt that market.
Also, GM ruined any chances of a diesel-friendly America back in the late 70's with weakly modified engines that couldn't handle the compression -- most of them blew up within 30,000 miles.
NOx and particulates are the only concern. Otherwise, they're more efficient with a smaller displacment.