Will HD really storm DVDs? 6 years isn't all that much time, especially considering that even today CD-Rs are more popular for data storage in consumer PCs than DVD-Rs. However, according to Kagan Research, by 2012 high-capacity optical media will encompass over half of the market:

“In 2006, the bulk of the $16.9 billion revenue will come from standard-definition DVD ($16.8 billion). By 2009, VHS will be virtually extinct and high-definition DVD revenue should grow to more than $2.6 billion as the format war works itself out, either via one winning format or a combination HD DVD/Blu-ray player being introduced to the market,” said Wade Holden, an analyst with Kagan Research.
It goes on further to state that by 2015, more than 68% share is expected. Is that realistic? It's been well over 10 years since the introduction of the first generation CD burners, and while DVD burners are sold more often, they are often used to burn CDs over DVDs.