The MC encoder in Vegas (and all SoFo/Sony products) is built in. The vresion number listed in the MC encoder window isn't the actuatul version. So, we can't download an update from the MC site (which stinks). I'm sure SoFO/Sony will release an update just to compete against Premiere Pro, but they probley say anything. :)
Time for another anology. While Vegas comes with a version of the MC encoder, it isn't the same version you can download from the MC site.
Just like with stock car racing, they start with some "stock" car, supposedly right off some car dealer's lot, but surely the machanics of each driver have tuned the car to get the most out of engine, suspension, tires, etc..
So too with the MC endcoder that comes with Vegas. Its a "tuned" version reworked to work best with Vegas. It ain't broke, don't tyr to fix it.