im bumping cause im in the same dilemma. ive done alot of research on these two cameras now and here is what i have found:
gl2 low light shooting is disgraceful compared to vx2000. the 2000's CCD's are 1/3" compared to the gl2's 1/4" CCD which allows more film grain in. the 2000 in low light produces next to no grain and requires no exposure gain where the gl2 requires full open aperture, 18+ gain, and still produces a very grainey picture.
functionality is generally the same in both, but the gl2 is more user friendly when it comes to fast adjustments. there are white balance and exposure preset buttons specifically for the one function where with the vx there is a button for white balance, a button for exposure and so on and you have to adjust it from there.
audio seems to be a problem with the vx2000. it gives off a shallow hiss, but there is a way to completely bypass this with an external mic. the hissing is nothing big, and you only will hear it if you are shooting in doors, but it is still present. the gl2 has been rated better audio overall.
when it comes to daylight, gl2 takes the cash. the gl2 gives 410 000 pixel image where vx is at 380 000. the image on gl2 is slightly sharper, and if you are only planning on shooting in daylight, this sun gun is for you. the gl2 has better optics (better color due to flourite, 20:1 vs. vx2000 12:1), and also gives you -30fps (frames per second)progressive scan, where vx2000 is only half that.
one other thing i have read is that the vx2000 autofocus is one of the fastest, smoothest, and most remarkable of the DV cameras. this is especially nice if you require autofocus for fast shooting in low light, because everyone knows that autofocus is a big nono in low light shooting. i have to try it out sometime.
all in all i am leading towards the vx2000 because i plan on doing lots of low-light shooting...outdoors. so the ambient noise will completely overpower the shallow hiss. anyways thats just my review of my research.
sources:
http://netscape.com.com/Canon_GL2/4864-6500_7-20224838.html?ctype=msgid&messageSiteID=7&messageID=849924&cval=849924
http://reviews.cnet.com/Sony_DCR_VX2000/4505-6500_7-6145072.html
http://digitalfilmmaker.net/gl2-review.html
http://reviews.cnet.com/Canon_GL2/4505-6500_7-20224838.html
and many, many more.