I like the first movie a lot better. You're introduced to the characters, there's a great battle (not much character development here, either) but it just made more sense to me. The plot was easier to follow and without so many contrived plot devices. The characters were more likeable and easier to relate to... at least that's how I felt.

I also just noticed this;
When Mudflap & Skids are an icecream truck, they have a phallus shaped popsicle on the side of the van and a "Suck this Decepticons!" on their paint job. Something like that... I probably paraphrased it, but same idea. >>