I don't mouse over to the corner of the screen in all but my laziest moments; but sometimes I happen to only have one hand on they keyboard (perhaps I was just closing a tab in Firefox, or upvoting a comment on Hacker News?). It so happens I'm right-handed, and so my mouse is on my right side, leaving my left hand in the perfect position for the windows key.

My common experience is to press the windows key and mouse around to click. While I proudly tout myself as a keyboard-primary user (and this is still the case. I use the keyboard as my sole tool in many more cases than some of my co-workers), I still happen to use the mouse from time to time and this is an example of it.

Also, when you're using an interface that has such accessible buttons, you tend to learn the general area of buttons, so it's not so much "scanning" as it is "oh yeah, that one repository is about here on the screen, let me swing my mouse over there and click it". The large buttons, again, help make that easier;* so, I don't quite have the same experience.* *

For my less-commonly used applications, I do follow the [windows key] enough text to load a program, usually the whole first word in its name because I type around 90-100 wpm and it's easier for me to type words than sub-sequences of letters [enter]; but it's rather surprising how much I've found myself actually adding apps to the start menu because I find clicking easier. Again, this is just from my personal experience, YMMV.

* I'm not a usability engineer, but I've read an article or two that talks about how difficult actions are for a user, and precision vs speed comes up.

edit:

* * As an example of this experience in progress, you probably know where commonly-clicked icons are on your desktop, if you happen to use your desktop to hold frequently edited documents or shortcuts. If someone re-arranged your icons, you'd be slower because they would no longer be in their previous, familiar locations.

From parent of your response:

    >Mouse over on the bottom left of the screen + Click + Wait for Metro interface to pan into view

Please, please, please, please do something about that bottom left corner mouse crap. I use a Windows Server 2012 VPS via Azure and that is the one thing that drives me insane when managing the server. Not getting a response until my mouse disappears from sight seems so wrong. It sours me on the entire OS almost. I don't understand why the server OS was shackled with the Metro interface, it's horrible for that use case.

You don't have to move to click the little start menu preview, you don't even have to wait for the preview to show up, you just bring your mouse to the corner and click. There's no aiming, just "throw mouse to corner and click". as commented by sukuriant

I guess mousing over to the corner is not so easy when you're in a non-fullscreen remote desktop: the mouse doesn't stop at the corner.

The great thing is that with the Start Screen the first scenario still works and anecdotally is faster for me than the Windows 7 Start Menu.

Actually, on Metro that's:

Window Key + "Su" + Click Sublime Text 2 -> Sublime Text 2 is open

EDIT: sukuriant has informed me that actually you can still just press Enter. So it's EXACTLY the same as before!

Enter still works

Ah, sorry, didn't have Windows 8 to hand, that was from memory. So it's the same sequence of commands!

Correct! I think I would have died if I couldn't still do my favorite win7 practices of "start, type, enter" for EVERYTHING. Ctrl + Shift + enter also works for running the program as an admin :)