Originally posted by: wuduhel
do any of these applications omit commercials while recording like TiVo does?
Just to clarify, TiVo does NOTHING to omit commercials while recording. The best you can do with TiVo is to program the forward button to skip forward 30 seconds at a time, which simply makes skipping over commercials a little easier.
Older versions of ReplayTV (version 45XX and 50XX) used to have a feature called "Commercial Advance", which tried to detect commercials automatically and skip over them automatically. Due to legal problems, ReplayTV has removed this feature from the newer 55XX models. They have, however, implemented a new feature called Show|Nav. This analyzes the recording to figure out different "segments" of the show based on scene changes etc, and then allows you to jump over entire segments at a time. Since the entire commercial portion is kinda like a segment, you could, theoretically jump over the entire commercial segment as soon as it starts.
BeyondTV and MythTV both implement a strategy similar to this Show|Nav, which, I think, they call SmartSkip or something like that. Unfortunately I didn't get to try this out since it was not available in the version I tried, so I am not sure how well this works.
SageTV allows you to program two different types of forward/reverse actions and you can program the amount of time each press of the button jumps at a time. Using this, it usually takes only one press of a "long" forward jump to skip over commercial segments. It is very easy to use.