I actually use this a lot just to get at the intellisense for all my variables etc ! Why type them out when the IDE is happy to do it for you?!

Personally, I think if you are extending a class or are designing a class that could be extended in future, it's good practice to clarify the scope of everything.

If it's a sealed class that doesn't inherit anything, I may omit this here & there, it's definitely self explanatory.