The thing is that the static pressure is very important for push fans but not so important for pull fans (I read this information from Corsair George). Pull is not as efficient as push is. I honestly cannot say what the temp difference would be between push and pull.
Remember that Corsair designed the H100 specifically for their cases. If you did set it up for push/intake you would get a positive pressure in your case which is desirable to keep dust from entering through all the little cracks and seams in the case. Of course, I would recommend getting a dust filter to put on your H100 fans.
I had the same problem you are having. I wanted exhaust, but because of the way the H100 and 600T are set up, with just one set of fans the only way you can get exhaust working is with pull (fans on the top with the rad inside).
What I ended up doing is cutting another 120mm fan hole at the front of the case on the top. This let me move the H100 rad one fan length toward the front of the case into the top drive bay (I have a two bay fan controller in my top two bays and it's only 1/2 length so it does not cause a problem with the H100). This allowed four fans so I could have push/pull exhaust. Not everyone will want to do that though. It was a lot of work, and did require cutting a big hole in the top of the case, but it turned out really sweet and works well. The top grill/cover still fits too so you can't even tell there's a big hole (you can't see the hole at all even with the top grill removed).
The thing is, if I had of decided I didn't want to mod my case for push/pull, I think I would have gone with intake/push and put a really beefy case fan on the back for exhaust. If you go into some of the other water cooler threads you can ask around and see if anyone has tested push vs pull. Maybe you're fine the way you are, but I was under the impression that pull by itself is not the best way to go.
Does your video card exhaust into the case or out the back? This is another thing to consider. Corsair George has mentioned that if your card exhausts into the case and you're using the top fans as intake, you can set up your front fan as exhaust and have a reverse flow. I think I have a couple of links that may help you decide:
Here's one where George mentions using the top fans as intake, and some on air flow:
Here's one on the two different types of exhaust video cards use and reversing your flow to compensate for internal video card exhaust:
Both link posts are at toward the bottom of the pages.
After reading all of this, I decided to mod my case for push/pull. I really thought about it for about a week before making the decision, but I'm happy with how it turned out. If you decide to change your fan orientation, be sure to add a little better fan on the back. It seems to me if that fan was beefed up a little it would do a good job of pulling the H100 exhaust out the back of the case while the front 200mm fan can provide fresh air coming in. Don't forget that fans on a rad don't give you their full rated air flow because they have to push through the rad. I'm sure a single good 120mm fan on the back would be adequate to handle exhaust if you reversed your H100 fans.
Tough decision you have to make. Let us know what you decide, and if you do decide to go with push/intake could you do us a favor? Take a screen shot of your CPU and GPU temps under load (Prime 95 and Furmark if you can) before you change (a half hour test is good), then reorient your fans and do the same test again. Do it with the controller set to max. It would help others to make the same decision you're considering right now.
Here is a site given to me for a comparison of push/pull and shrouds.
Although they are comparing high speed 38mm fans to low speed 25mm fans, they seem to think that pull is better at low speed and push is better at high speed. If this is true, since you're using low speed you should be fine with pull.Edited by Mergatroid - 9/15/11 at 7:05pm