The good: The Lumia has a superb screen it really is super smooth and bright. The OS is a a big positive for me all the major apps are there and I like the live tiles, the people hub is a brilliant addition and improves the facebook experience no end. The Phone is beautiful to look at and hold. The camera is good if not spectacular.
The bad: The battery life is poor but Nokia say there is a fix coming coming so hopefully that will be arriving ASAP. 32gb would have been nice for a high end phone. Podcast support is poor for non-US owners which still grates (OS problem though)
I have upgraded from an iphone 3GS and couldnt be happier. Glad to be rid of the grid icons and Nokia have done a superb job on build quality.