I've used the Canon GL-2, Sony VX2000, and "own" a GL-1 and XL-1 (my dad technically owns them, but I have access to them whenever...). I honestly prefer the XL-1 because it is a larger camera with more weight on the lense side so it is easier to maintain a steady shot when shooting from a moving boat. The XL-1 is pretty expensive but when the XL-2 arrives you can assume that both the XL-1 and XL-1s will drop in price. Also you have the (rather expensive) option of using interchangable lenses. There are several lenses including an $800ish wide angle lense (not 100% sure on the price though) available, and I was able to use this lense when shooting footage at the Malibu Open. I'm almost done w/ the vid and it should be on this site hopefully in the next few weeks if you are curious about the optics or what not...
comments on the GL-1: great camera, but no manual audio controls. This really isn't a big deal but it bugs me after using the rest of the aformentioned cameras that DO have manual audio controls...
GL-2: got to use this when the GL-1 was in for service for ALL of last summer (thanks Fry's Electronics
). Manual audio controls have been added, the camera is a bit longer, and the color sensitivity is a bit different (cooler colors).
VX2000: If memory serves me correctly, the CCD's on this camera are larger than any of Canon's cameras (well the ones mentioned here), but the optics arent as great (again, I could be wrong, this is from an article I read awhile back). I don't know if there is any truth to this but the XL-1's standard glass is pretty much as large as the VX2000 itself. Nonetheless the VX2000 is a great camera and would be my second choice behind the XL-1 (though that may be because I'm more used to the XL-1). Also remember that this camera has been replaced with the VX2100 so it should be cheaper than the $3000 price tag it had when it was the latest and greatest.
so my opinion: go with the XL-1, then VX2000, then GL-2, then GL-1.