I assume since you're asking that you don't care about having a physical keyboard. Other than the keyboard and being available on Verizon today, I don't see a single advantage the Droid has over the Nexus One. If you can wait, I probably would. If you can't, the Droid is still a great phone.
Nexus one has better hardware as someone stated. Only other main difference is that the Moto Droid has the physical keyboard. Personally I wish I would have waited to get the Nexus One because I hate the physical keyboard on this phone.
Problem is, no one really knows when the N1 will be released on Verizon. Spring 2010 could easily translate into second quarter and release dates are commonly pushed back. So take that into consideration.
Personally, I would wait for the Nexus 1. You will get faster updates, faster hardware. With the Droid, you have to go through the update pains (which we are currently going thru), and the only advantage is the physical keyboard, which is barely used.
Let's not forget the Droid is built like a tank...it's a solid phone. I believe the N1 is more light weight and "flimsier" feel to it...(I am speaking based on what I have read and not from having experience with the N1)...
My contract is up at the end of the month...I am planning on buying a droid....whenever the nexus one comes to verizon would I be able to sell my droid and activate the nexus one or is the contract tied to the droid itself? Would this cause any problems or is it perfectly ok? Sorry if this is a dumb question or one that has already been asked 10000 times. Thanks