You know both the Blu-Ray and HD-DVD formats may fail.

[thunderhawk]

Not if they put more HD content on the market. And they will.
Within the coming years, the HD market will explode. Look for yourself.

And yes, DVD did have more advantages over VHS then BD will over DVD... It was smaller, the picture quality was better and they didn't require rewinding.
BD now, offers better picture quality and more space. BUT BD offers HD and DVD doesn't.

However...

Despite DVD's better quality, VHS is still widely used in home recording of television programs, due to the large installed base and the lower cost of VHS recorders. The commercial success of DVD recording and re-writing has been hindered by a number of factors including:-

* A reputation for being temperamental and occasionally unreliable.
* Shorter recording time: 2 hours on a single-layer disc (up to 4 or 6 hours with higher compression) versus 3 (NTSC) or 5 (PAL/SECAM) hours (up to 15 hours using PAL EP) on a VHS tape. Dual layer recorders and media have not yet become commonplace.
* Buyers are wary of another format war amongst the five formats (-R, +R, -RW, +RW, -RAM).
http://en.wikipedia.org/wiki/VHS

I really hope the above 3 factors won't go up for Blu-ray Disc...