The title pretty much says it all. I've downloaded and installed Adobe Photoshop CS6 and have entered the serial number I was provided at the time of purchase but am receiving an error message that reads "The serial number you entered is invalid. Please try again. If the problem persists, contact Customer Support."
Ugh. Y'know what? Nevermind. Turns out that I'd actually purchase Photoshop CS5. I'm marking this issue as resolved.