How Bloggers Comment System Lead to Being Mistaken For a Groupon Shill
rachelbaker.meHmm... The problem is, that first bit DOES sound like she whole-heartedly supports Groupon by calling it 'guaranteed'. Even after reading the entire thing (not the shortened one) a few times, I wasn't sure what her stance was.
Groupon is guaranteed marketing in the sense that people will purchase the Groupon offer. Is Groupon the best and most effective marketing tool...that will reach your target audience? No.
It's the vagueness of the original statement that is the problem. If you had said 'Groupon is guaranteed to get customers to enter your building', then that would be one thing. But you just said it was 'guaranteed marketing', which probably means something different than you intended. It sounds like you support them.
Personally, I think they have a good service, provided you know what you're doing, know how you're going to keep these new customers, etc etc. If you don't, it's a disaster waiting to happen.