"I don’t think you’re going to see that really long six month, seven month lag, like you saw in the updates from 1.5 to 2.1, simply because it’s a less severe change."
This was a direct quote from the interview. Sounds more like it won't be long
Based on how quick Froyo was made somewhat compatible with the Evo 4G, I think that an official HTC Sense version will probably be ready by October. I don't think it will take until "around X-mas".
I read somewhere that the upcoming OTA update will improve battery life. Apparently the EVO had a similar update and the battery life drastically improved.