[corin_]

RT is still useful when you want to add a comment. For example...

There are exceptions to this, but generally agree RT @natesm Don't use "RT". Use proper retweeting.

[ceejayoz]

I typically see that done like this in my Twitter crowd...

> There are exceptions to this, but generally agree "@natesm Don't use 'RT'. Use proper retweeting."

[corin_]

I see both pretty evenly, I prefer the RT way personally, but both work for sure.