After perusing the "Sporepedia" for a bit, you might start to wonder "Can my lowly Windows-based PC or Mac handle this much awesomeness?" Maxis responds with a thorough set of Spore minimum system requirements for the release platform of your choice. And they're not at all unreasonable! Windows gamers, you're up first, Mac gamers, you're after the jump.
Windows XP
2.0 GHz P4 processor or equivalent
512 MB RAM
A 128 MB Video Card, with support for Pixel Shader 2.0
At least 6 GB of hard drive space
Windows Vista
2.0 GHz P4 processor or equivalent
768 MB RAM
A 128 MB Video Card, with support for Pixel Shader 2.0
At least 6 GB of hard drive space
Mac OS X
Mac OS X 10.5.3 Leopard or higher
Intel Core Duo Processor
1024 MB RAM
ATI X1600 or NVidia 7300 GT with 128 MB of Video RAM, or Intel Integrated GMA X3100
At least 4.7GB of hard drive space for installation, plus additional space for creations.
The official site warns that the Mac disk space requirements for Spore are subject to change. It also has a fairly exhaustive list of supported video cards for both camps. You good to go? I am!
Spore Specs [Official Site]