Proposals for a HTML 5 specification promise to bring in embedded media and APIs in a highly simple and accessible manner, relegating the need for browser-specific workarounds. However, it's the proper implementation that can never be promised.
The proposed HTML5 specification is the brainchild of the W3C and the Web Hypertext Application Technology Working Group, commonly known as the WHATWG, pronounced "What working group." This is a group made up of people from Opera, Apple, Mozilla, and Microsoft, and its emphasis is on the transformation of the Web from a largely static repository for text and images (the Web of today) into a platform for interoperable applications far more inviting and easy to develop for than current standards allow.
But it is the implementation of these standards in a uniform manner that is the real crux of the issue. Already, Mozilla and Opera have announced support for new HTML tags for embedding videos. This will enable the browsers to play videos as long as the browser supports the codec.
This would also allow users to use open-source tools to embed video (e.g. video encoded in Ogg Theora). Adobe with its Flash Format and Microsoft with its Media Player are doubtful to support the open-source format.
Here's a preview of the HTML 5 Spec, available at List Apart.
The WHATWG has set aside a time frame of 10 - 15 years for roll out of the new specification. The time line aside, will the clash of interest among the stake holders ever lead to a uniform implementation of the spec?