Fit and finish is superb.
Speeds are another league.
Screen size is perfect, i thought it would be weird, i even stood opposed to the change on the design of the 4S for a while, but it's great, not too big, but not drastically different.
Quality is as would be expected from Apple, and they improved the features the phone already shined with (screen quality, camera, iOS).
...so, is it really that much better than the 4S? The answer is unquestionably yes.
UPDATE: I went to a nearby Verizon store to check out the iPhone 5 and my impressions are as follows:
1. It is a gorgeous looking device, especially the black one.
2. The display is bigger than I thought it would be and I liked it a lot. The size of the display is perfect.
3. The weight of it is uncomfortably light and that was with the security cable attached to it. I'm not sure I like that. It didn't feel cheap or not well-made, but it did feel hollow and left me with the *impression* that it was too fragile. I hope that made sense.
4. The speed of the device is as you said. It is indeed fast in all areas. I'm not talking from a technical viewpoint, but from a real world viewpoint. Is it "way faster" than the 4S? Not in my opinion, but it is faster. No doubt about that.
5. The length & thinness of the device is great and appreciated.
6. LTE is fast as heck! I am very impressed with that. Being that it seems faster than Wi-Fi, people will want to use it more and thus will consume much more of their allotted data. I'd definitely have to up my data plan...
Having said that, will I now go out and buy it? I haven't decided yet. Did it wow me? No, but it did exceed my expectations. If I bought it, do I think I will be happy with it? No doubt about it.
My only gripe is its weight. I wish it was a tad bit heavier. Anyway, that's my 2 cents...