I seem to have a weird glitch where the crow item doesn't work right on the vita version. For example, my last match had fusion, crate, and hedghog grenade set on high. I never got a fusion bomb, rarely saw a crate, and got a ton of grenades and crows... and I didn't have crows turned on. This type of thing has happened several times really.
Apart from that, and the interface (Which I'm slightly more biased towards the PS3 one) there is no noticable difference. However for some reason the graphics seem to be either better and worse at certain moments on the vita version. I'll run into incidents where I can clearly see some low res jags, or a strange polygon-like thing stickying out around character models, but at other times (usually at super close zoom) the graphics will look even better than on the PS3.... and a lot brighter to. Weird but just my observations. I love either version thanks to how similar they are and its amazing that I can take the game on the go, yet play it on the big screen whenever I'm home.