Helvetica is a beautiful font and IMO timeless.
I wouldn't stop myself using it if it work just because it might seem over used. Context is everything.
I do a fair amount of work for BMW, their house font is a slight variation of Helvetica (they got fed up paying each time!).
I don't think it's overrated but it is overused/poorly used. People seem to think they can use it 'straight from the box' but the truth is you can't (poor kerning for a start). I think used properly it will remain timeless, just like its documentary (well worth a watch).
Good points Harry. I was almost tempted to argue but your totally right that far too many designs use Helvetica straight out of the box (same with any font really).
As time goes on though I've found kerning has become less of an issue it terms of font evaluation. It becomes something that you can adjust in your head while previewing suitable fonts.
Nice sites BTW, Web Design+ especially. Lovely white space mmmmm