They'll be offering "Commander in Chief", "Alias", "Lost", "Desperate Housewives" and others.

If it goes well I'm sure they'll start charging even with the comercials included, but it does sound like a good way to catch up with 'Lost' if the picture quality is good enough.

Disney to Place ABC TV Shows Free on the Internet

Three of those shows are already available on iTunes for a charge, so it doesn't look like this is an experiment into that area. More likely, they're looking at some on-demand feature that still gives their advertisers a venue. Notice that the commercials are non-skippable.

It'd be interesting to know how much ABC gets from the advertisers for those three 1-minute commercials. It's possible that the advertisers would pay more for a captive audience than ABC would get for charging the end user for the service.

Warner Bros. has their own version of this service for older shows:
http://television.aol.com/in2tv