My main stance with DLC is that I don't want hving or not having it to interfere with normal gameplay.

I'm OK with seeing an ad for it in the main menu, even a "buy DLC" button right there if need be, whatever.

But I would ahte to downlaod a park in Tycoon and think I'm about to edit it like normal but suddenly getting "BZZZZ You need the DLC to do this!" would infuriate me.

What I always remember is Dragon Age Origins. I love the game and I do own all of the DLC for it, but if you didn't have DLC it SUCKED. Listen to this:

You go to your camp, a guy is there who will tell you this long winding story about his ancestor's castle and how he wants to go there and clear it out and reclaim it. If you listen to the story and say "OK Let's go, I'll help you out!" he's like "whoa slow down, you need to buy the bioware points and then spend them on the Wardens Castle DLC if you want to do this quest!!"

If I don't have the DLC, don't tease me and screw with me. It's OK if you advertise it, but don't interrupt normal gameplay with what's essentially a sales pitch.