Following Facebook’s Places announcement popular location service Foursquare saw a spike in user signups. This comes according to a Tweet by Fourqsquare co-founder Dennis Crowley: “Just heard from The @HarryH that today was @foursquare’s biggest day ever in terms of new user signups.” @HarryH is the Twitter account for Foursquare’s lead engineer Harry Heymann. While many [...]