I agree that multitasking is better in the N900. Not only due to a better interface but also due to its 1 GB of application memory. The Droid will run out of memory faster and crawl to its knees with a few applications open, while the N900 will keep working just fine with a lot more applications loaded.

Also, what about storage? How much room for installing applications is there in the Droid? How much data storage?

The N900 can run applications written in Python with a GTK or Qt interface! That makes the N900 a lot more like a desktop computer in my eyes, and makes it a lot easier for people to program for it. There are already hordes of developers trained in those technologies. Many more than there are Java developers. And Dalvik is not really Java. So even if you know Java you need to first understand the differences beteen real Java and Dalvik.

Finally, I agree that Google's Navigatio is a big plus for the Droid. But, the GPS is not the main reason I am looking for this type of device, it is merely a bonus - to me. And it is not like Navigation is completely missing from the N900. So, I can live without Google Nav. It may be different for you. Get what is best for *you*.