Courtesy of the Windows Live Digital Memories Experience blog come instructions on clearing tag suggestions in Windows Live Photo Gallery.
I'm glad for this because I've fat fingered a few tags into WLPG and have wanted to remove them for a while. It's basically an instruction for digging into the registry to delete the key(s) you wish to remove. I'm sure this will be cleaned up in a future release to make it easy to remove tag suggestions via the UI.
BTW, I love Windows Live Photo Gallery and have been using it as my photo organizing tool for months now. More to come on this in future posts...