It doesn't matter. There are literary precedents for both.
The National Association for Good Grammar (NAGG) seems to be helping fuel this "debate," which seems to me an attempt promote themselves as a legitimate authority on grammar when the reality is, there is no "authority" on grammar. There are hundreds of "authorities" on grammar; hardly any of them agree with each other on lots of things; and all of them collectively prove that none of them are "right."
Say it how you want, "twenty-ten" or "two thousand and ten" neither is more or less correct and anyone who tells you otherwise is full of themselves.
Interestingly enough, there are three things to notice about how people pronounce the year.
In general, men tend to group numbers together. Dates, addresses, telephone numbers -- what ever it is, they're more likely to say 3511 as thirty-five eleven. So, for the current year, men most probably more often say twenty ten.
Women, on the other hand, look at numbers singularly, as in the above address example, they would say 3511 as three-five-one-one. Therefore, they're more likely to say 2010 as two thousand ten.
Old people, let's say Baby Boomers or Traditionalists over 50 years of age, for whatever reason, tend to speak dates entirely differently. They don't say twenty-ten or two thousand ten; they're more likely to say two oh ten. Don't ask me why, they just do.
I have said many times that what you seek in the bible you shall find. Still I see the same few verses being thrown around in support of one opinion or another. I wonder why those particular verses stick...