I've had my Discover More card for almost 20 months, and it's limit has stayed the same. Of course for a year and a half it was left in the sock drawer. Well a couple months ago out of necessity I put a $600 balance on there and carried it for two months and just paid it off 2 weeks ago and have been using the card for purchases since.
I was getting down reading about people getting CLIs and realized that I haven't gotten a CLI for two years on ANY card, lol. But I've never requested a CLI in my life, so I decided to go login to Discover and request a CLI. Low and behold, when I login to my account I got my first auto CLI out of Discover after 19 months. They added $600 when my last statement cut on the 17th. It's pretty meager, but I don't need any more credit than I have, and they were already tied with Chase for my highest balance ($3000), and at the time of my original app, my highest limit was $2500, which they exceeded. Now they're holding true to form and reclaiming the highest limit in my wallet, or... sockdrawer.
Moral of the story is, Discover seems to be really good about taking a risk and exceeding your highest limit. I think $3600 is the most I can ask for on a student's income of ~$20k My Discover card bumped chase freedom to the sockdrawer due to their excellent customer service and customer loyalty that I've experienced, even though freedom's rewards are slightly better.
Congratulations, thrasher865! Discover is a great card, and it sounds as if you treated them right, so they returned the favor.
(I melted the plastic on mine this month from heavy usage, hope they'll appreciate me, too!)
On a similar note, I have put a lot of money through them these last few weeks and I too hope they return the favor. Next month is my 1 year anniversary as well.