Pete's ScratchPad has a great geeky review of the Canon XL-H1, testing it against motion artifacting as well as the SD lenses (older 20X and 3X). He kindly provides some MPEGs as well as frame grabs and lens tests.
HDForIndies has a very negative review of a screening of some XL-H1 footage by Canon. Apparently there were some problems with the 24F demo that Canon is providing so it may not be representative.
My own complaint? The Canon XL-H1 uses center-weighted metering for motion video. It has a tendency to overexpose and given the sensor's tendency to bloom, this is a Bad Thing. I found myself having to dial back the aperture during the conference yesterday. Also, the little $1600 Sony has a live histogram, the $9000 Canon doesn't?