I agree the Blu-Ray is the superior format on the capacity levels, but I think HD DVD has proven that they are better with interactive content, internet connectivity, PIP commentary.
Right now for Blu-ray to have PIP commentary, they have encode the same movie with commentaries in it. Basically, they will need 2 movies on the same disc, one with commentary, and one without commentary (this might change in the future, but for now, that is what they are doing). While HD DVD only needs 1 movie and they mix the PIP into the movies, which cuts down the need for more room. That means, I can switch PIP on and off without interrupting the movie. Also, the internet connectivity that is standard on all HD DVD players means that they can update the firmware without the need of burning a disc or you can download additional footage. Maybe even getting a director's cut footage to mix with your HD DVD standard movie. I think it is also clear the Blu-ray was not ready for the market and BDA simply release the Blu-Ray player because of pressure from HD DVD. The interactivity from Java is not standardized on the first generation stand a lone players. IIRC, there are 3 java formats for Blu-Ray and they are not compatible with each other. So now interactive movie will not be useable on those $1000 first gen Blu-ray players. In that sense, I think Toshiba is a smarter company than Sony and i rather give my money to them. This is why I think HD DVD is actually the superior tech to Blu-Ray.
Both formats delivers equal HD PQ and AQ, but HD DVD is cheaper than Blu-Ray. So you get the same content, but one format is cheaper with more interactivity. 50 gb or 30gb, I pretty sure you won't be able to tell the difference 99% of the time.
With that all said, I'll enjoy either format, but I rather see HD DVD come out on top than Blu-Ray. I understand that if you are a PS3 owner, you would naturally want Blu-Ray to win, so I won't contest that, but I rather Sony just release a cheaper PS3 without an Blu-Ray player. The fact that a PS3 cost $600 is not a good thing to us gamers.