I'm pretty familiar with C&V stuff but I just bought a threadless fork for my bike and have to start shopping for a threadless headset. Whats the main difference between a typical threadless headset and an integrated threadless headset?

threads.

Non-integrated threadless headsets use external cups which you press into the frame just as you would for a threaded headset.
Integrated headsets have ''cups" that are built into the inside of the headtube for the bearings to sit on.
Check out the Chris King website. They do a pretty good job of explaining the differences, IIRC.

Well there is that (looking at post 2) but a little bit more.

Threadless headsets allow you to use clamp on stems as opposed to quills. Quills are elegant but not as available as in the past. OTOH threadless stems are legion at all price points. Also, if your fork has a carbon steer tube there is no threaded option.

As far as "regular" threadless and integrated the main difference, IMO, is aesthetics though I'm sure there's other reasons that can be presented as well. I have both. Actually, I have all 3 as I have retro racers with threaded. They all do the job when you get right to it.

You guys apparently didn't read the question. He wasn't asking about threaded versus threadless. He was asking about integrated versus non-integrated, and plasticmaam pretty much nailed it.

There is also Zero Stack, and a ton of other standards, it's very confusing.

Chris King has a slightly biased take on things. I wouldn't say that integrated headsets are necessarily great (they work fine, but the multitude of incompatible standards is quite irritating), but they are certainly not the harbingers of doom and destruction that Chris King makes them out to be. They're headsets. Some of them are damn nice headsets. Some of them suck. Most of them work just fine. That is the way of things.

Different manufacturers that offer an integrated headset tout their superiority over other types of headsets. My concern would be the difficulty in replacing an integrated headset when it requires it perhaps to find it very difficult and/or costly to find and buy.

you worry unnecessarily. there are loads of integrated headsets and they are as cheap or expensive as you are willing to pay. cane creek, fsa make pretty cheap ones.

Cool...thanks for the info.