I feel that Nokia is more concerned with fast money rather than long money.
By releasing so many devices in such a short span while providing minimal support of the operation system they are basically flooding the market hoping you buy one of their devices, maybe two. This will get a lot of revenue, but if it continues more and more people will see through this practice and become disgruntled.
Imagine if Apple kept releasing new Iphones instead of upgrading and supporting the current software - imagine the outcry. Well this is what Nokia is doing.
Here we are with 3 different devices in 2 1/2 years, many differnt software versions, some work with some devices and not others. They are now going to release a 4th device soon - what will this device be compatable with?
In my opinion I may one day buy an Ipod if they continue to show that they do stand behind their product, they do consider future growth of the product (if Nokia had considered future growth, we wouldn't have so many incompatable OS's out now).