I just got one 2 weeks ago because it was free. My wife has the expensive Samsung Galaxy IIs whereas I just upgraded from a Samsung Gravity. This review was thorough, but I have a few nits to pick. First off, I find I like the bar for back and search better than the capacitive buttons since it is easier to locate without looking and I like the tactile feel. Unlike the reviewer I have had no trouble at all with the camera button. Further, his camera review was rather shallow. If you search you can find a detailed comparison of this camera and others in the same price range for Windows. This camera performed worst in Sunlight, but best in dim light settings, contrary to what the reviewer found. I would trust the much more detailed comparo.
Further, the search defaulting to Bing is no biggie since it is butt simple to set up a Live tile that goes right to Google or whatever search you wish - that button is unecessary and I wish they had set it to forward the way you have on a browser.
The Nokia Drive is great since you incur no roaming or Web data usage fees to download maps as you would for Google maps. It is a big download (1.8 GB) as reviewed.
As to screen, well yes, the Galaxy IIs has a much better screen but it also costs much more so you get what you pay for.
As for comparisons between iOS, Android and Mango Windows 7.5 - I don't see a huge difference from the end-user point of view. There is an icon - you hit it - and it does some useful (or not useful) thing. Obviously, there are far fewer apps. I read that there are about 500K apps for the iPhone, 250K for Android and only about 50K for Windows. That may be true, but since I don't use my phone for games I have found, so far, all the apps that I needed (stocks, flashlight, weblinks, scientific calculator, navigation, an app for creating live tiles ...).
I have found the 4G web downloads as fast as the Galaxy IIs and I think this is a limitation of your network coverage where you are - not the phone. I think it is rare to find a place where you can actually download at the maximum speed.
All in all - for a free or $50 phone - it is a fine device.