I like it, though perhaps it's better suited to the meetup organizers list lw-organizers@googlegroups.com. Unconditionally, you should post it there.
I've requested membership with that group, but I doubt I'll be given access in time to post it and give people a reasonable chance to use it. Good idea, tho.
Restaurant.com is perpetually offering specials like this if you get on their mailing list, ranging from 50-80% off the stated price. So don't worry about timing too much.
From here:
If the consensus is that this is too much like spam, I'll remove it, but it seemed like it'd be of interest to meetup groups who meet at restaurants.