Foursquare today is the most popular mobile checkin app in Vilnius, Lithuania. While not everyone here can afford the iPhone - many people are using Foursquare on their Blackberry.
Point of note - Blackberry App World is not available in Lithuania and so people are using hacks to install this.
Here’s a couple of screenshots from Checkin Mania confirming the number of venues is great in Foursquare vs Gowalla in the central old town area. Right now, some quick checks and stalking reveals that frequent checkin is being driven by international travellers and business users along with staff from mobile operators.
Ok I suggested the science of increasing number of venues as a measure of usage for these location based social networks - and believe this holds true in Vilnius - right now venues and places is not at the granular detail I’ve been seeing in London and certainly its very easy to add a venue and become mayor.
Anyone interested in working or a trial of social media marketing in Vilnius let me know