In the new photos app from Google, I wrote "teddy bears" in the search box, and all the pictures I had ever taken of my son his teddy suddenly popped up. It is a feature that is spoken about at length by one of my favourite tech jounalists, Andy Ihnatko, in his weekly podcast The Ihnatko Almanac. There is no doubt that this app raises the bar in terms of elegance, and in under the hood search and recognition capabilities. It can organise your photos into intuitive and sensible collections without the user doing a thing.
Yet in exchange for this freebee, Google wants something in return - access to all of your data. What if the government demanded of Google everything it had? Perhaps in the name of counter terrorism, the agencies of state could be granted access to the photos of millions of random Mohammeds and Faisals, and be able to track the whereabouts of innocent civilians. What sacrifices are we willing to make to have the convenience of our photos on all of our devices, and how can we reasonably measure what that sacrifice might ever be? These are the sorts of dilemmas Ihnatko enages with in his perspective-laden podcast, which concludes that it is good for people to make their own minds up, with a little education thrown in to assist.
There is also the other potential problem of storage, and whether we can ever be certain that our photos are safe. Google reserves the right to use your photos in anyway it sees fit. No one can guarantee that a cloud service will stay open for business anymore than they can presume a hard drive with a terabyte of memories can continue to work indefinitely.
My advice is to back up locally and remotely, and to do something truly retro - print them off. Lest precious precious memories, or teddies for that matter, are lost or misused.