Adwords is increasingly becoming a black box where advertisers aren't really encouraged to understand what is going on. In all lot of cases they seem to want to deny advertisers information. I'm not sure what the thinking behind this all is but I suspect one of the biggest reasons is leveraging data without exposing it to advertisers or allowing them to do creepy seeming stuff.
That doesn't mean Google won't buy them or won't want to provide these kinds of services. They do provide a crappy product in this category which has very few use-cases these days.
Anyway $28m considering the SAAS/SME model should be viable at a range of scales. I wonder if they are planning any big changes that require this kind of cash. Maybe something freemium or a new product that will take a lot of time before it can be profitable. Just speculating.