The Android emulator is a bit sluggish. For some devices, like the Motorola Droid and the Nexus One, the app runs faster in the actual device than the emulator. This is a problem when testing games and visual effects.
How do you make the emulator run as fast as possible? I've been toying with its parameters but haven't found a configuration that shows a noticeable improvement yet.
How do you make the emulator run as fast as possible?
Buy a faster computer.
The emulator is running actual ARM opcodes. It uses qemu, which is a virtualization system akin to a VirtualBox or VMWare, to accomplish this. That approach maximizes the fidelity between the emulator and real-world devices. Its cost is the ARM->Intel opcode conversion. The only way to significantly speed that up is to speed up the CPU that runs the emulator.
I have not done an exhaustive analysis, but I do not get the sense that qemu and the emulator use multiple cores. Hence, "a faster computer" is governed more by the speed of a single core than how many cores it has.
To the extent possible, I would develop "games and visual effects" on actual Android hardware, using the emulator for testing configurations that you do not own (e.g., QVGA). For example, I've done a reasonable amount of work on video playback apps, and I only bother developing those on hardware, because video playback (and presumably some games) requires graphics acceleration to work well, and qemu does not have a graphics accelerator AFAICT.