I find the transition between it and the traditional desktop rather jarring. While one as some degree of control over the positioning of Metro tiles, it is not complete control.

The tiles can only be arranged in columns of two; there are no odd numbers of columsn allowed. Tiles autoarrange within a column from the top down; you cannot position a tile at the bottom of column where it would be close to the hot spot that brings up the Start screen. Even if you could force tiles to the bottom of a column, there is a minimum distance between the lowest tile in a column and the bottom left corner that activates the Start screen.

If MS insists on this model of autoarranging tiles, it should put the Start hot spot in the UPPER left, closest to where the first tiles are anchored.

I also found it quite cumbersome to reduce the size of some of the tiles. Tiles come in 'single wide' and 'double wide' sizes; I have no idea what determines the default size. They can be made larger or smaller by right-clicking, but only one at a time. I wanted to 'Make Smaller' all of the double-wide tiles. I could select multiples with CTRL+Right-click, but the 'Make Smaller' option disappears if you select more than one at a time. I recognize this is most likely a one-time operation for each time; still, having to individually shrink eight or ten of them quickly became annoying.

I haven't figured out yet how to create new tiles. I loaded Office as one user, and tiles populated the desktop automatically. However, when I switched to another user, the tiles for Office apps were not there. I don't know how to start apps that I know are there; I haven't yet found a 'Run' or a 'Start, All Programs' equivalent.