Let me try to answer some of the outstanding questions, although we can't 100% confirm everything at the moment.
What is the difference between cross-play and cross-saves and are you trying to support both for the vita?
There's a support page on playstation.com, which explains the cross-platform feature pretty well.
support.us.playstation.com/app/answers/d...-cross-platform-play
As the support page indicates, there are different types of cross-platform features. The one that we are looking into is cross-save support. This means that you can start your game on either system (PS3/Vita), save your progress and then continue playing on your other system.
will this support the ability to upload my save data to the rainbowgames.com server via 3G?
You will be able to upload your game stats to our servers. I don't think there will be any difference between your connection mode (WiFi/3G) but we haven't dug so deep into technical restrictions yet.
have you tried implementing touch to the vita port?
This would require a complete rework of the game's UI. We haven't completely ruled out touch features yet but it's less likely.
Will add-on content we bought apply to the vita port?
They will most likely be compatible to another. This means that add-ons that you have purchased for the PS3 version will also work with the Vita release and vice verse.
and will the vita have add-on content for those who don't have the ps3 version to cross save into the vita?
The previous question basically already answers this. We are also considering new add-ons for the Vita launch but this hasn't been decided yet.
Any predictions as to when this will be out?
For sure in 2013 but it's hard to make an estimate. Hopefully it won't be later than Q3/2013.
are you going to sell this at the same cost as the ps3 version?
Pricing hasn't been decided yet but for sure it won't be more expensive than the PS3 release. We are also looking into discount options for owners of the PS3 version.
will you have a ps3+vita bundle?
Most likely, yes.