I don't know if I agree with Dell making a mistake. There is a very solid reason why they went with Alienware. We may not know all of the details, but in the end - they just expanded into a large market that just a small line of XPS's could not compete with (in my opinion).
On a similar note - and one that I have recently made mention to to Hypersonic. The nice thing about this deal is that users of all financial levels could get a good system. In a lot of cases, and I will use Hypersonic as an example, there is not a low cost power house desktop available. Both of the boxes available still cost around $4k. They are awesome systems - don't get me wrong. But after buying a notebook for $3-4k, trying to get a desktop just makes it less likely.
With the Dell/Alienware deal - they could take it where the xtreme systems are the Alienware and the next level are the XPSs. NOt sure how it will pan out - especially with that new sweet 600 with the flames.

Also going to be cool to see how the two families mend together. When you have two companies competing and then come together, there is going to be some heartache. But I think it will be cool in the end.
I was talking with some contacts I have with Dell Federal Services and told them to bring the paperwork to make me the Alienware Federal Rep. They laughed and said that would be cool. They know my gaming tastes don't meet the federal systems well.

I guess more will come in the next 12 months!