I do get a very brief audio delay when restarting the computer, or starting MCE, but it's minimal and not an issue.
I don't really watch regular TV anymore, but I tested going between channels using my tuners in MCE and I did not notice a delay at all (although MCE is not the fastest at changing channels).
There is no delay when playing music from my NAS or when streaming MOG (via Airplay to the HTPC).
So, for me is a non-issue.
But, even if I was experiencing delays when switching channels, I'd rather have Trinnov, than have no delays and have to go back to Audyssey....