I have an elite concierge and she's been very helpful as well.
I like being able to call the number and get someone to help right away instead of having to go through the automated system and being placed on hold. Also the ability to communicate via email has also been helpful.
They've helped with reservations when I wasn't able to do it over the phone, adjusting rates, apply RC card certs for lounge upgrade, calling properties to make sure I get a room upgrade, fighting for me when an upgrade is denied,...

I like the program and I've used it since I was invited.