Nothing has been able to supplant video pre-roll as the dominant video ad format. This ClickZ article says that advertisers are defaulting to pre-roll in the media recession as a “tried and true” format.
That’s despite lots of empirical evidence that consumers don’t like it. I can tell you that from a personal standpoint I mute it or click away when pre-roll appears. My daughter has been watching lots of the Olympics coverage online and the volume of pre-roll advertising that NBC is pumping into the video is totally obnoxious. In every single instance we mute the ads.
Yet it would appear to be here to stay given the inability of anyone else to come up with a viable replacement. Even YouTube is reportedly going to introduce it after a much-publicized launch last year of “overlays” that were supposed to avoid the consumer experience disruptions of pre-roll.