Dropbox was (and is) a great implementation. Photostream is basically hit or miss as to whether it will sync a photo to my personal photostream, and we wait for hours for "shared" photostreams to pick up.

Meanwhile, when I share anything in my Dropbox, personal or shared, it basically syncs real time - as in, while we are talking on a chat, I drop a file into my shared folder, and seemingly at the same time I say, "I dropped a file in our shared folder" the person at the other end says, "Yup, I got it"

It's beyond me why Apple still can't get photostream to be that responsive with their resources and control over the platforms.

Dropbox had to figure out when a file landed in a OS X folder - Apple controls the operating systems!

Good point.