For my two sense, I think Scot is right in his response. I attended DTS and was not accepted at any American universities I applied to and attended a British university. One element that has not been discussed is the ecomonic angle. American universities especially the top end schools (e.g. Duke, Notre Dame, etc) don't need students. They have 100 applicants for 2 spots each year. Furthermore, one has to score extremely well on the GRE before one is even given a siff. These kind of odds make it extremely difficult to get into the program no matter who you are.
On the other hand, as has been well documented, British universities are in desperate financial crises. And many of the more well-known schools are dependent on North American students to bolster their bottom line. The economics of the situation make it easier for an evangelical student to get accepted into a British university and that has nothing to do with a non-liberal bias. This is not to say that the British system is not more "open" in ways pointed out by both Dan and Scot. Indeed it is and this is a strength of a British research degree: You're on your own with regard to your research.
One last personal note. I have not felt slighted at the SBL meetings because of my evangelical pedigree. I am a co-chair of the Matthew section and have had very positive engagement with non-evangelicals-many of whom I consider good friends. I think it is not so much that you are an evangelical, it is how you wear it that really matters.