This tool is absolutely brilliant, true IDE AI. You can kiss Code Completion good bye. ReSharper goes the extra miles that the built-in code re-factoring and intelligence tools in Visual Studio doesn't. Code optimization, Code completion, Code Formatting, Coding standards etc.. whatever you can think of is there.
From my personal experience using this tool: Go Get this now! Programming will have a different taste. It is like having some expert look at your code while you are coding and giving you advice about it.