Bay deserves the jokes he gets but i don't agree with the "he's the worst director working in the industry right now" statement many give, he's kind of in the middle.
The Rock was good and fun, probably his best film, Armageddon was a mixed bag with good and bad aspects, still it was entertaining, Transformers 1 was better than Armageddon but not as good as The Rock.
Pearl Harbor was bad, it had some good points but completelly missed the point of what it was supposed to be and tried to be Titanic without a decent romance. Transformers 2 was aweful, and Transformers 3 was for me a major guilty pleasure, i loved the experience of watching it in 3D on the big screen and the city war was well done but the film itself was bad.
Have yet to watch The Island, the Bad Boys movies and Pain & Gain.
He's a strong director when it comes to knowing how to put a film together and has some creativity in the way he shots things, but he thinks too much with his d*** and doesn't pay enough attention to his scripts, leading to dumb characters, and racist jokes. In other words he's good on the technical level but not in the rest.
He's also what i like to call a bulls***r, while his characters are flat he gives them steriotypes and tells you what they are, he gives you romance but at the same time it's non existente, and emotion is fabricated. This leads to most of the usual cinema going audience thinking they're waching an emotional film with a deep story, when the "development" is actually almost minimal and little more than filler, this is painfully obvious with Pearl Harbor. Armageddon is also known for making men cry.
I'll give the credit to Mr.Bay for making entertaining films, but he works better when he's under a leash, as The Rock proved.