To clarify, Snapdragon is the name for the platform. The processor core is called Scorpion which is based off the A8 architecture. This processor is paired up with an Imageon GPU along with an ISP and DSP. The OMAP3 found in the DROID is paired up with an SGX GPU. While the OMAP3 isn't as stout as the Snap's Scorpion, the GPU tends to be the weak point of the that combo where as the SGX GPU is very good, though also clocked slower. At the end of the day, it comes down to integration. Which combination and integration of SoC design works best. Benchmark tests for the N1 aren't out yet, but the HD2 which has the same hardware was bested by the iPhone running an OMAP3/SGX combo in virtually every graphics test except for a few integer-based tests where the Snap shines.
The short answer after a long one is: You're fine. The DROID's SoC is potent and will run and continue to run in many mobile platforms even after the N1's release. Snap is just the latest fad for marketing purposes. Don't get me wrong, it's very, very capable, but it won't render what you have obsolete.