Foursquare and Gowalla are continously improving and updating their services. Latest news:

Foursquare is cracking down on cheaters. If your phone’s GPS determines that you’re not close to where you want to check in, you are not rewarded any points or mayorships.

Unfortunately, this doesn’t work with my iPhone, it won’t let me check into my Office, even though I am sitting in it. Looking at Google Maps, though, it seems that my GPS does indeed place me correctly.

This is a good move nevertheless. In the last month during my trip to Thailand I could well check into locations here in Hamburg whenever I wanted, enabling me to keep up the battle for the mayorship of your office here…

Gowalla in the meantime adds realtime feeds and activity streams based on the PubSubHubbub protocoll. This should enbale much more interesting mashup opportunities (since it is apparently faster than the user-specific RSS feeds that Foursquare uses). If this is the case it could yield an important differentiator for Gowalla, which to me seems to desparatly need something to effectively compete with the larger competitor Foursquare.