== Negatives ==
* Clashes with Gates during CEO transition of power: http://online.wsj.com/article/SB121261241035146237.html
* Developer relations / motivational speaking (thanks mathattack): https://www.youtube.com/watch?v=wvsboPUjrGc
* Employee retention (thanks JonnieCache, Ziomislaw): http://www.smh.com.au/news/technology/microsoft-ceo-im-going...
* Windows Phone: http://www.forbes.com/sites/markrogowsky/2013/07/18/if-you-h...
* IPTV platform Microsoft Mediaroom (thanks nixy): http://www.theregister.co.uk/2012/02/03/bt_vision_upgrade/
* Vista (thanks balakk, danieldk)
* Internet Explorer neglect and market share declines.
== Mixed ==
* Failed Yahoo acquisition (thanks michaelpinto, seanmcdirmid, throwaway1979): http://www.microsoft.com/en-us/news/press/2008/may08/05-03le...
== Positives ==
* Xbox / games division (thanks benihana)
* Enterprise successes (thanks gregd, facorreia)
* Facebook investment (thanks riffraff)
[edits: updates per reply comment suggestions]