What is the correct way to pronounce 2010?

Answer 1

We're talking about how many years have passed since the birth of Christ: two thousand and ten years.

The most common now is "Two thousand ten" but the form "Twenty ten" is also correct when the context is clear, as was the earlier year nineteen ten. The years 2001 through 2009 are still mainly two thousand and one. It is possible that twenty-oh-one may eventually become the standard, but it did not for one thousand nine. The 22nd century on uses the historical standard, e.g. twenty-one-oh-one, because it is not an even thousand.