There are some downsides, like a lack of a front-facing camera, blurry video recording, and a camera that doesn't impress as much as Nokia boasts, but overall it's one of the best Windows Phones around.
Vivid AMOLED screen; Solid design and curved glass; Good custom apps; Windows Phone 7.5 UI is easy to use
No front-facing camera; No microSD; Single-core processor; Poor video quality; No HSPA+ or 4G support; Unlocked in the US