TechDigest spent a bit of time with the M600 and posted their reactions to this next-generation UIQ phone. One important point? It's better than the Blackberry 7100 and supports multiple push-email solutions, including RIMs. That means this thing is patent-proof, accepting email from multiple server types.
They did have a minor issue with the keyboard but the touch-screen and scroll wheel scored high in terms of usability.
Hands on with the Sony Ericsson M600 [TechDigest]