No surprises here. The key is whether you are a consumer or a business, what elements of these types of review are valuable to you? What are you going to do about it?
For me a lot of it comes down to which app you will use and why. I use Foursquare a lot so, I will be more likely to see a tip . It’s quick and I can see if there are friends in the neighbourhood, it rarely occurs to me to even open Yelp. I was of half a mind to delete it, but I have enough space on my phone to leave it there.
If I’m looking for a quick coffee or bite to eat, a tip about a nice dish, dirty toilets, great or slow service are all I need and I’ll find those in Twitter. If I was looking to take someone out to a nice meal and wanted to treat them to a great evening, maybe I’d give Yelp a go, but that’s a rare occassion for me and we have a favourites that already go the extra mile, so we often frequent them (and mention them on Foursquare:).
Not knocking Yelp, there were previous phases in my life where I might have used Yelp a lot more than I do now. I’m mostly in the I’m in a hurry generation.