I am an amateur cameraman and have been working around codecs for the last 6 years. I compared WMV-HD, H.264, DivX-HD and XviD-HD (profile) on my Sony HDR-FX1 shootings. My result: H.264 best by far, but you gotta work out the best codec settings, then DivX-HD, same thing, then XviD-HD (couldn't fit the proper settings to work as I needed) and last WMV-HD (you need quite higher bitrates for the same quality as the mentioned or you see aberations and macroblock artifacts). Because the main point has always been reducing size of MPEG-2/HD TS stream onto something with as little quality drop as possible yet much smaller, I will work with H.264 HD custom profile, until something better comes up. My setting is 1440x1080i (4:3) pixel AR 1:1, variable bitrate round 4.5 Mb, keyframe boost 60%, B-frame reduction 40%, bitrate variability 40%, automatic quantizers 1-51 at step-by-4, spatial encoding, 2-3 unbiased B-frames, all partitions and transforms, adaptive weighted biprediction, slight deblocking, and no CABAC (it is troublesome when combining files and editing too).
At these settings I get best results with the same bitrate of all mentioned. Try it out and see.