The whole point is that Stephen Colbert based his character and his show mostly on O'Reilly and his ilk. See Rush Limbaugh.

The Colbert Repor(t) is fucking hilarious, but it's pure satire...as was said above, the talk show host Colbert portrays on his show is just that, a portrayal. Stephen Colbert the man is simply a comedian who's done some great work over the years, and continues to do so.

I expect their meeting to be absolutely hilarious, practically the opposite of what happened when Bill showed up on the Daily Show.