So the built in 500 gig hard drive can't be replaced which is fine.now you can use an external hard drive with it like the wiiu.and iam sure we can install games to the exterernal drive also great idea now who will use it

Not me, I'm content with 500 GB. Plus I only play one game at a time, and if worse comes to worse, I'll delete games off my HDD.

The 50 gig downloads are pretty big.  You are going have to plan a day in advance if you want to play a deleted game..

I expect at some point down the line (2015 or 2016) I'll be picking up a 1TB external hard drive to use with my X1. The combined 1.5TB will probably be enough for me through the entire generation, as I'll probably delete some of my games from the hard drive when I'm done with them.

That's because of sheer size and slow downloads right? For an install on the 360 it's about 10 minutes, for a retail install. It's not optimal, but it can deal with it. 

Has it been added already? MS said it wouldn't be ready at launch.

OT: Yes, I plan on getting a 2-3TB drive as I hate deleting full games off of my hdd. I still have yaris and alone in the dark GOD installed, both of which are crap and will never get played again.

Yes, getting and external drive in a size of 3TB perhaps, just so that I can have all the games installed and not be forced to delete. I have just started using an external drive in my 250GB elite, but MS really screwed that up by only allowing such a small space to be added.

I'll probably have to since 500 GB clearly isn't going to be enough space.

You know "xbone1" is the same as saying "xb one one" right?