Mine started at $300 and is now $4100 through auto CLIs. it is a great card and they will keep raisning your limits. Take care of it and it will take care of you.
Mine (the Discover co-brand if that matters) started at $4200 a year and a half ago and is now at $6200. Not bad for a GEMB card.
Congrats on the CLI, OP!
I too have the Discover; pre approval at checkout for $4400 accepted in June '09 and I just got a $1000 bump in December. I hope this card will be a regular CLI grantor.