I just want to say thank you to those that recommended the sippy cup with the attached straw. Wyatt really took to them. I tested the straw theory out on him with some cherry limeade from Sonic and to my surprise he totally sucked it down. I couldn't believe he knew how to do it. So I went out and bought him the straw type cups from Nuby and he's a suckin' machine. It's awesome. I'm so happy that we got that straightened out.
So, if any of you are having problems with the sippy cup thing, check out the Nuby cups. I got mine from target for like 3 bucks a cup.