One reason that I preferred Hitchens to Dawkins

Hitchens seemed to have a positive attitude towards debate, and seemed to be willing to enjoy friendship with some of his debate opponents. There was even a documentary about a debate series with Hitchens involved... (got it on DVD if you're interested in borrowing):

Dawkins on the other hand, didn't seem quite so eager, refusing to engage in debate with certain people on the topic of theism - which lead to criticism from some fellow skeptics and a somewhat amusing bus ad campaign "There’s probably no Dawkins. Now stop worrying and enjoy Oct 25th at the Sheldonian Theatre" parodying the the atheist bus ads run in recent years.

The video of the Oxford debate at Oxford can be found online BTW. The person organizing that debate on runs a fairly interesting weekly debate show which seems to attract a fair number of both Christians and skeptics. Previous people the host has interviewed include Dawkins himself as well as Christopher Hitchen's brother (amidst a whole pile of others). The Peter Hitchens episode was quite interesting just to compare the personalities of the two Hitchenses - they're actually quite alike even though Peter Hitchens is in the evangelical camp.