I've been using Windows 8 across a number of different workstations and VMs, and noticed a strange behaviour with the start menu that I'm starting to think is a bug.
In Windows 7, the quickest way to launch an application was to hit the start menu and just start typing. With enough characters input, the program you wanted was selected as the first item found and you could hit Enter to run it. The point being that when you hit the 'Start' key, the search box was always blank.
In Windows 8, I have the same experience, most of the time. However, there are occasions where I'll hit the Start key and my old search is still populated in the search box. For example, if I've previously run Skype by hitting start, typing 'skype' and hitting Enter, a few minutes later I'll press 'Start', start typing (lets say, 'word' to run MS Word) and find that my new search is being appended to the word 'skype'. This will obviously result in no hits, as I have no applications installed called 'skypeword'. I then have to clear the search box manually, and then I can type to search.
Is this a bug, or as designed? Pretty much everyone else I've spoken to who runs Win 8 as a power user hasn't encountered this, so I wonder if it's some behavious I'm using which is causing this. From what I can see, it's a fairly annoying regression.