REI Arete ASL

I just bought this new tent from REI and when I set it up the 3rd pole (over the door) caused the floor of the tent between the tabs
where this pole is inserted to be pulled up as if the tent was sitting on top of a 2x4 on it's side. Is this normal for a dome tent? Maybe I'm just paranoid but it seems weird that the tension is so great that the floor is not laying flat in this area. Bad design? Bad tent? Anyone?

I have no idea? I'd call rei and ask them. I would be concerned that to much tension would cause a tear. Tents usualy sag a little over night or when it rains, so the extra tension now might be for this reason? But, I'd definitly call rei

The answer to your question is "Yes", it's fairly normal. You see it in a lot of tents, like the North Face Mountain Tent. It reflects the strength of the poles being used. However, after you've set it up a couple of times, the poles are likely to have a little "pre-bend", which would reduce the tension across the floor. Also, once you put a sleeping pad or two in the tent, that "ridge" should disappear.
Shifting gears, the Arete looks like a terrific tent for colder situations. We live in Florida, and camp in NC and Georgia where it gets into the 30s at night. That's "cold" for us! The Arete looks like the answer for us. I like that you can remove (or install) the fabric across the door, if you want to eliminate breezes on an especially cold night. And $250 is a pretty darned good price, compared to, say, a Marmot Alpinist or MH Trango. Not to mention the weight difference...

I saw this same effect with the corners on a couple of dome or freestanding tents I have looked at, including a SD Omega. It gives the tent a sort of rounded bottom look unless it is staked down.

Tents need to be under tension, so the fabric doesn't flap around, so I suspect this is fairly common with certain designs. I think my tent ( a five pole design) does this as well, but I can't remember. I have only used in in winter, so on snow, this would be less obvious.

I wouldn't worry about it. Once you stake it down and load you and your gear into it, you probably won't even notice it.

I'll jump in with everyone else, It is a common occurance with most tents particularly with dome & half dome tents. it's nothing to worry about. Let us know how you like it after some use, I am thinking about adding it to my list of next tents to consider or the new REI Cirque ASL 2 Tent.