A little follow-up on this post:
As a test run, I redeemed for an Amazon gift card on Checkpoints. It arrived in my email a week later, so they get a +1 for a reasonable redemption time.
Good and bad news on Shopkick: There seem to be more easy "kicks" for walking by a store. Just do a search for all of the nearby stores and you'll get a few when you walk by them. There are also more points available for scanning items. I work in downtown Boston, so I am pretty much surrounded. Bad news: The updated site is confusing, eliminated the levels you can earn and seems to offer fewer kicks. Hey, it's all free, but I wouldn't go too far out of my way for it.
I'm still waiting on my first Ibotta purchase. Unfortunately, supermarkets aren't linked yet, which is difficult for a site that deals mostly with food items.