There's also a general faith that Pinterest will actually keep their service open in a few years. With Google, it's a crap-shoot if it gets any updates 6 months from now.
EDIT: after reading more about "Keen," and trying it a bit, my bet is that it will be like Google Spaces - an interesting idea with some utility, but will die out because they won't have "Google scale" engagement to keep funding it.
EDIT 2: I also learned that Google Collections is the exact same thing. This is Hangouts vs. Allo vs. Duo vs. Spaces all over again.
this is someone's project to get noticed for being innovative and moved on to somewhere else with more money and then this gets staffed with people not on the fast track who will try their best to get out of it and finally it will close down and if anyone has been suckered into using it they will write an article about how Google closed it down and then HN will repeat the ever expanding list of things Google has closed down. Something may have just made me cynical about Google products though.