I think this is a great idea - definitely doesn't seem like it was meant to be a cash-grab to me: it's not a lot different from a "pre-order" option, with the ability to put the funding toward anything you want, and it definitely seems to have been motivated by trying to gain meaningful market research data.
I definitely didn't see the results they're getting coming! Seems like it's a much more accurate gauge of what paying customers are interested in, than suggestions from us vocal forum users, and the more traditional polls. Or, at least, it's painting a different picture of what paying customers are interested in, than the other sources of data that WGA have been using.
The biggest surprise for me, really, is the popularity of the cavalry kits - I just don't game with cavalry very often, and don't know anyone who does, so I never really trusted the anecdotal popularity of cavalry in request threads and the like. That does seem to be an area where the forums, polls, and Vox Populi seem to agree. Same thing with the Deathfields heavy/command kits: I'm a bit surprised how popular those seem to be in Vox Populi, but that seems to be doing well.
And, I'm a bit surprised that some of the fantasy and sci-fi options aren't more popular. Seems like Napoleonic historics are carrying a lot of the weight, followed up relatively distantly by dark ages subjects.
I'll wait a bit and see how stable the future looks for me, and if I feel comfortable with it, I think I'll add a little of my weight to Vox Populi - I, for one, do have a soft spot for the niche subjects like moderns, near-future, sci-fi, Victorian, pulp, and the like! :)