Swift key 3 was really the best one I've ever tried. It predicts your sentences based on your past messages but I haven't been sprung for the paid version because my previous fav is still free and that's Go Keyboard. Good prediction & easily customized to personality. As you can see I'm using a theme that matches well with ICS.
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I use the SwiftKey 3 and have to say that it the best I have seen. The predictions are as if the keyboard is plugged into your brain. You can also change the height of the keys in portrait and landscape view. The area for me that is lacking is the themes.
Smart Keyboard Pro is the best one for me! This too has type prediction and a lot of themes as well. Keys are adjustable and I like that you can calibrate the keyboard to your touch, which makes for a lot of less mistakes when typing fast.