I've had an S3 HD Tivo for about 3.5years now. Still going strong, now with a 1TB drive. Got a new Premier about 4 months ago and it now has a 2TB drive in it. I love them. I'm on Time Warner here.
Hard to say about the channel updates, there is a notice in the messages folder when it happens, but I have no way of knowing when the change actually took place.
There is a standby function but I never use it. It's accessed through the menu. If it's plugged in, it's on.
User interface is far superior to any cable DVR that I've seen, plus you get all the online extras, Netflix, Pandora, remote scheduling and season pass administration, etc. The TiVo updates it's software automatically, you do not have a choice not to. Updates to the Premier are happening every 2-4 months at the moment. IP control is awesome, no RS232, no problem at all with IR.
They are still not perfect. They use a multistream cable card and you need a tuning adapter if your cable company uses SDV. No On Demand capability. The tuning adapter and TiVo still need to be rebooted occasionally. Far less than the Scientific Atlanta boxes that we use here in my opinion. If you look here:[Link: tivocommunity.com]
You will see that some people have not had the same good experience that I've had.