Recently tried out Feedspot, a thoroughly unremarkable RSS reader. Logged in with Google account, and the service appears now to have emailed a bunch of (but apparently not all) my contacts with an invite email, without permission:http://i.imgur.com/qiIlovw.png
Just thought I'd warn everyone. There's also no way to remove your account (although I've contacted them asking them to do so). Stay away from this one.