I read through some of their explanation - and it does sound like a "sign-in using Facebook". In general, I'm not comfortable with that setup unless I trust both parties equally, and trust they will not share/access information between them. Even though it's just an API that's being used to access the Google credentials, it's something I'm not comfortable with. Even though it's an automated process, who can say for sure that they will never try to leverage that automated process to give themselves access to my Google account? By accepting their request for "permission to access Google credentials" I'm giving them the ability to access my account, and I don't see any type of legal language or User Agreement that would prevent them from doing so.
Maybe I'll just create a "zombie" Google account and start using it for all these sites that insist on piggy-backing on Google's authentication system...
I use chrome and Log in to chrome with my google account. Let me keep all my favorites and history accross multiple workstations.
When I login to the feedly app, a gui pops up saying that the app is trying to access:
1) basic account info:
-View your name, public profile URL, and photo
-View your gender and birthdate
-View your country, language, and timezone
2) Manage Google Reader:
-View and manage your subscriptions, likes, and shares
3)View Email address
I may be missing something, but it didn't seem like feedly would be getting my password, and only handling things I didn't care that it would handle.