I posted this over at Remote Central but I figure a cross post won't hurt:
I just picked up my One from Best Buy. As others have said, it says coming soon, but mine had just gotten theirs today. I'm coming from an 880.
First impressions are good, the touch screen is very sharp and easy to use. When you have more than one page, a small arrow on the sides. Also there are two buttons on the bottom of the screen. If you are in an activity, the right button is the device list, and vice versa. All the buttons are 2x3 including favorites, and you can have 4 pages for 24 total favorites. (Side note about favorites, the desktop software now has built in icons for Fox stations. It may have been this way for a while, but first time I have noticed it.) As for everyones favorite topic of colored buttons, they do work on the additional buttons. It appears to be the Label that you set for the button, not the actual function. EX: on my XBox360, If you set the label for a button to Y, the Yellow Y button shows up like we have seen in that right hand column. If you set the label to something else, if won't show, even if the button still sends the Y command. The only button icons I have stumbled on are the XBox labels and the Scientific Atlanta ABC buttons. It DOES NOT have the DirecTV color buttons, at least not that I have found.
The overall button layout is definitely an improvement over my 880. The raised buttons and the spacing will be much easier, once I learn the layout. The off button is a little small for my tastes. It feels a little wider, even though it is the same width. It seems like it is more oval shaped, where as the 880 feels more circular. It doesn't have the nice feet that the 880 has, so when you set it down it rocks a little. The USB port has a nice cover. Hopefully it won't fall off.
I am happy to report they redesigned the charging base. I'm have to replace my 880 because like so many others, I have a hard time getting it to charge. The One base only has two contacts, and the stick up further than the 880. Also the contacts on the bottom of the remote are much bigger.
Overall, very nice. Not a necessary upgrade to an 880, unless like me you are having problems, but definitely very nice.