Having a kid, my only complaint about my current M3 sedan is getting in and out of the rear, and the limited leg room. The M3 GT may take that complaint away, though I'd like to see what it has to give up.
I could be interested in it. The announcement that a 4 door M3 was going away by the time I'm shopping again pretty much had me looking elsewhere, mainly trying like hell to love the CTS-V sedan's looks. I'm already disapointed in the next gen M3 motor but I'm willing to try it out, as I would be willing to try out the M3 GT as well. At least if they do this, BMW will get me looking their way again.
08 GT500 convertible red package (Black w/ Red stripes) /Ford Racing Exhaust /Cold Air Induction 560hp
10 Porsche Cayenne GTS Black w/ Black Wheels 408hp
11 M3 Silverstone w/ Silver Novillo Leather /Tech /Premium /19" /DCT /Ipod 414hp