What makes a good MOBILE paysite tour?

It's a bit more than that. First you have to figure out who your audience is. Are you creating only for iPhone, or do you want to also reach BlackBerry, Droids, Palm Pre's, etc?

Then you have to create tours for each phone and then use the script to detect the device and send them to the right tour.

interesting... how do you test other than getting one for each phone?

You can use the various SDKs available for the platforms. They all run full emulators of the phone OS on your PC.

The main thing is to K.I.S.S. (keep it simple stupid)
TopBucks did a great job on theirs and I used it as my guide to building mine.

I didn't need to do several sites in several resolutions either. I built ONE mobile site and I own an ITouch, a Blackberry Storm, and a Droid.

Works perfectly on all of those.

And by the way, that one suggestion of using the SDK to put the OS on your PC is good for testing your vids. But it does NOT show the layout the same as it looks on the phone. Not even close. It doesn't show font sizes and spacing anywhere near the same.

I A/B'ed my Droid with the developers OS from the SDK and they looked completely different.

Take a look at claudia-marie.mobi to get an idea of what I'm talking about, and then pull it up on your phone. It's very simple, which is key for mobile. You don't want to have to try and navigate a lot on a mobile phone. You just want the basic "good" stuff readily available.

I don't suggest using emulators as they can return false positives. They are good for quick testing, but you really want to be on the actual device and play with the vids, where the text is placed, make sure the descriptions aren't all crazy, etc.

We do have phones in the office for all. Some employees are nice enough to let us use their BlackBerry or Palm Pre, however, BB is the biggest pain.

When you design for BB, you can't design for it in general. One has to be made for the Storm, one for Storm II, one for Curve. BB also works a bit differently as they require you to download it as they go through their own proxy. However, BB's memory can't hold entire episodes.

iTouches can vary from the iPhone, so don't use an iTouch and expect the same on the iPhone. As well, the iTouch users are vastly different than the iPhone users.