I ditched Windows search a long time ago. To me using the built in search feature is like trying to use Windows Media Player for all of your media needs. It only has the basic things an average computer user might need, but anything more than a basic search and it's worthless. Corpernic is the best out there, IMO. I even bought the Professional version for the computers at work.
With Win 7 it really doesn't matter where anything is located these days. Just start typing whatever you are looking for in the Start Menu search and it'll pop up in the start menu results. All you have to do is type one keyword like "Printers" or "Programs or "Network" and all of the control panel applets made for those types of items will pop up and 9 times out of 10 it'll be the first option. I can't tell you the last time I opened the control panel or clicked "All Programs" and scrolled through a list of apps to find one I'm looking for.
I also really like the Recent Items for each shortcut.
Favorites in Windows Explorer is great.
What the hell are libraries for? I understand their thinking behind them, but I haven't found a good use for them yet. I thought I had when I first started using Windows 7 but after trying to use them for a bit I didn't find them that useful.
About the only thing I don't like about it is UAC. Even though they gave us the ability to change how we interact with it, it still sucks.