Courtesy of Dave Zatz, TiVo is indeed pushing out support for H.264 for TiVo Series3 and TiVo HD owners (requires hardware support, sorry Series 2 owners). New service features include accessing YouTube, and CinemaNow will reportedly be available soon as well as the 2.4 update enables.
No official reports if this update will allow you to stream H.264 content from your home network though it would be a wise thing for TiVo to enable for enthusiasts.
In other news, Amazon.com is (re)launching their online store for movies and television called "Amazon Video on Demand" according to this NY Times article. This is a smart branding move on their part - most consumers (and industry types) understand the concept of VOD, and "Unbox" requires more explanation. Amazon's service will offer streaming and while it wasn't in the announcement, I'd expect this new update to work its way into the TiVo shortly where Amazon Unbox already exists. It's been confirmed to be available via Sony Bravia Internet Video Link but at $300, I'm skeptical this will have mass-market appeal.
Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.