Interesting article on why we shouldn't use Task Killers on Android

Not that I completely agree as per my observation, but interesting to read - especially the section which mentions: 
"On Android, having your RAM nearly full is a good thing. It means that when you relaunch an app you've previously opened, the app launches quickly and returns to its previous state. So while Android actually uses RAM efficiently, most users see that their RAM is full and assume that's what's slowing down their phone. In reality, your CPU—which is only used by apps that are actually active—is almost always the bottleneck."

Associating file types to an app in MAC

There doesn't seem to be one place like windows registry classes subclass or the file associations application where you can set the application to open a file of certain extension in Mac OS X.

If you select one file and click open with and select an App, it's associated to open that file only even if you select "Always open with". It doesn't set the open with app association for all files with that extension.

Easiest way (or is it the only way?) to do that seems to be this way:
Open File Info of a file of that extension. For e.g., to set all .sh to open in macvim, select any .sh file in Finder. Then Click Command I or right click -> File Info.
In the Open With section, select the app to open the file with
And importantly select the option "Change All". That's it - This should do.