1. Why would I hand over my photos to a third party, that, quite ostensibly, is capable of indexing and tagging it by face- and location-recognition and store on their storage. I used to trust Google with most of my information, but I've been slowly transitioning them away to either local, or a home-brew solution.
2. What I noticed for the first time is not the cool new shiny things, but the absence of Hangouts and Google+ features. Did they get completely abandoned, or are they to be covered later? It seems like a Google style to make some AI-enhanced or Google-flavored version of pre-existing service(be it RSS, social media, you name it), let it get hyped because "Google", then abandon it when it doesn't reach some internal target.
Honestly, while I definitely agree that they're all cool stuff, but I do not see myself using those features; it's more of a trust issues over convenience. Just my two cents.