Dunno. All new, one in beta. Given the intense competition for your photos, who knows who'll be left standing in one year?
Meanwhile, Dropbox has developed Carousel, and although it hasn't drastically cut costs in response to Google it's useful for a lot of stuff besides photos.
And there's Google and Picasaweb; tried and true. And good for other kinds of files as well.
And if you want to show photos, Flickr is still a decent deal. And Shutterfly, Behance, etc etc etc.
It all depends on your needs. Some work with lots of apps and have Lightroom and/or Aperture compatibility. Some don't do RAW.
About all anyone can say in response to such a vague question is "probably better than iCloud"