We sorta actually do have 4:2:2 digibeta support...
If you consider that Vegas lets you select a preferred capture application, it could easily be Digitools, and you just use that to talk to a digisuite board. (We won't be getting digibeta through a firewire card, of course.)
Vegas will happily edit the digibeta footage. The only element not available is PTT from the timeline. We can still render to 4:2:2 avi and print to tape using digitools.
This isn't to say that DV is not broadcast, either. Many stations and networks broadcast DV 24/7... I just visited three network affilliates who use DV exclusively on-air, so DV is truly broadcast quality. Digibeta may be better, but depending on your needs, DV may be just fine; it is for stations around the world.