RunKeeper announced a $10 million round of investments led by Spark Capital, which has also invested in Twitter, Tumblr, Foursquare, with participation from another new investor, AOL co-founder Steve Case's Revolution Ventures. Return backer OATV, the venture arm of O'Reilly Media, also participated in the new round. The Boston-based startup, which now has 14 employees, plans to use the funding...