Given your love of Hyundai, I'd be surprised if you didn't have the Elantra Touring in your top position if you are looking at wagons. Fully loaded for just over $20k and its more Euro wagon than US hatch. Way less than Mazda pricing and better fuel economy too. I scraped thoughts on WV's diesel wagon in favor of the Elantra Touring for my top choice for this summer when I get new wheels.
The Touring is most certainly on my radar, but not until the redesign with the new sedan engine that gets 40MPG highway. That's not supposed to happen until 2012.
I do appreciate a certain amount of 'fun' factor to balance out economy though. For the most part, Mazdas have a reputation of being more fun to drive. My wife's Mazda3 certainly is a fun ride. A Mazda6 wagon has more storage than an Elantra Touring. I'd be willing to sacrifice a bit of fuel economy if it was more fun to drive and offered better utility.