I'm thinking of starting a PbP in this setting after recently picking the Player's Guide to the Wilderlands and am wondering if anyone is running a campaign set it it?
Yes, I do. Have been doing so for some months (I was/am part of the design team.)
Are people using the suggested alternate XP progression chart?
I don't use 3e anymore, but when I did, I used this chart with lowered XP awards for non-plot related stuff. It worked well. I currently employ an evel slower progression rate.
Which, if any, of the alternate classes are you using
I had access to an earlier Amazon, which I used a lot (and ported to my current game), it's a beautiful example of genre emulation and innovative rules design. I "wing" alchemists and sages. The first are somewhat viable, but dealing with sages would be excessively complicated. I also think their "books" are too pricey for the granted benefits, especially when, in 3e, magic items give you an insane amount of skill points. Witches - I didn't find them suitable for my ideas about the millieu and never considered them. I dislike "sorcerer" types in general... And I removed prestige classes from the equation (with one exception).
Ditto for the alternate races (I like the setting for having distinct human races even in game terms)?
All PCs were ported from an older campaign, which meant they were "normal" humans... New characters did use some of the races - there was a Skandik, for example, and it worked nicely. NPCs, of course, were of all types. I forbid some - True Viridians (heh, who'd thought?

), Altanians and a few more.
Where do you base the campaign (anywhere besides in/around the City State?)?
The first campaign started in the City State area, around Warvick (I placed Rappan Athuk on the peninsula to the east), and later moved along the coast to Barbarian Altanis (I like this map - no, I
really really really love it, absolutely, oh yes I do). It is currently on hold... When I get around to it, it will be about Dark Tower, an old and great Paul Jaquays/Judges Guild module.
The second, with evil lowlifes, is also set around Warvick (pretty different from the official, though - much smaller and ruled by Skandiks). The characters subjugated a small settlement and established themselves as its lords. Currently exploring the area.
Do you pay strict attention to the tech level rules?
I use them as guidelines. Generally, higher TL itmes may be bought imported but not produced, which makes trade very important. It is also possible to hire experts whose ability is equal to a higher TL on a temporal basis. I created a sort of "long term encounter" chart for this and other things, which you can access from JG's site (called "Taxes&Death"). It is more for older rulesets, but may be appropriate for 3e.
What adventures, if any are you using?
Mostly my own, but some older JG fare also comes in (Book of Treasure Maps, Dark Tower, Thieves of Fortress Badabaskor, etc.), I expanded a lot of settlements, islands and ruins to full adventures... I will likely type up some and release them to the public when the boxed set comes out. Necro's modules are also good, mostly the smaller or "episodic ones". I used Rappan Athuk, Tomb of Abysthor and some others. You should probably download the supplemental material - RA's Wilderness is very usable to steal ideas from for your wilderness. Crucible of Freya is less good but still usable for scavenging. There are also a few AEG mini-pamphlets (I only have two but will buy the collection they are set to release), a bit hit or miss, but again, usable.
Comment: you have only seen the tip of the iceberg. Haw haw haw!
