Bear in mind, I have no particular love for the company (I'm typing this on my rMBP right now). But I like to acknowledge good work when it happens. I know that all of these can be argued against, and some of my choices below are easy to argue as not great software -- but compared to any other competitor is still better (e.g. if mail and calendars are so easy why aren't there loads of Outlook/Exchange competitors?)
- Remote Desktop is really good. VNC is "ok" but my God I miss Remote Desktop in the Apple world
- Pretty much any MS-Office product, highlights are Excel, Powerpoint, and Outlook. (Much better on Windows machines than Macs BTW, in much the same way iTunes is better on Macs than Windows)
- Visio, not without it's quirks but other competitors are all "ok"
- Project - are there any serious competitors?
- OneNote
- Explorer, I've yet to see a file manager as good. It's lightyears beyond the abomination that is Finder for example. I could go on, but it's probably one of the reasons alternative media organizers are not as common on Windows machines as Macs
- Visual Studio - I can see some arguments one way or the other, but it really is a world-class dev environment.
- Online Office apps are easily the best office web apps by far
- SQL Server is actually very good.
- Flight Simulator
now outdated, but top of the game for many years
- Midtown Madness as an open world driving game
- Encarta was awesome
- Halo series
and hardware
- the Xbox systems
- really nice mice and keyboards
- Xbox controllers
- Kinect
- the surface pro is actually a pretty amazing full fledged portable PC, I'd put one up against an Air anytime, except it has the slight edge of the much more robust Windows software ecosystem