The two new Lumia phones both look very good. The Nokia Lumia 800 for a start looks fantastic. With a 3.7 inch AMOLED display, a huge 1.4GHz single core Snapdragon processor and 16GB of internal storage (along with the 25GB of free cloud storage that comes with all WP7 phones via SkyDrive) it can compete with most other smartphones. It also has a 1GB RAM and a wonderful 8 megapixel camera with 720p HD recording and Carl Zeiss optics. The Lumia 800 is looking to be a great phone.
The Lumia 710 is the mid range Nokia WP7 device but in spite of this it still seems to have impressive internal hardware. With the same display as the 800. The camera is a decent 5 megapixel, and it also has the same 1.4 GHz procesor. However from the pictures we have seen the 710 looks quite cheap and tacky compared to the sleek look of the 800. However the idea of the swappable covers is good and the fact that Nokia are making them the same colours as the tiles on the home screen for Windows Phone is pretty good too.
Both Lumia phones look to be successful in my opinion.