I am by no means an expert, but will offer any help or advice that I can. I will lay out a set of steps that I performed to make mine work.
Sorry for the long post. Please post any questions.
I Pwned it using Pwnagetool 2.0.2 to FW 2.0.1
Here is where I started: I had an old fw1.1.1 otb and I JB on 1.1.2 with one of the first methods. I think it was the installer method. I was a little curious and apprehensive about starting on 1.1.2JB to Pwn to the new 2.0.1. It worked flawlessly. I used the OSX pwnage 2.0 guide here:
Pwnage 2.0 Guide - ModMyiFone - Wiki
I pretty much followed this guide step by step. It was very good and helpful.
1. I connected my iphone to itunes and then downloaded fw 2.0.1. I backuped my contacts, calendars and everything else while it was downloading.
2. After it downloaded, I opened PwnageTool and hit expert mode. Selected iPhone 1st gen. Let it find FW 2.0.1. If you have both fw's 2.0.0 and 2.0.1, give it a little longer it will find both but choose 2.0.1
3. In the guide, it says to uncheck activate under the general tab, and uncheck unlock baseband if you are a legit at&t customer. I am a legit at&t, so I was hesitant but it worked fine. The only problem I have here, and somebody else might have an answer, is it said that at the end after itunes restores and the phone starts back up for a legit at&t you should not see the bootneuter screen. I still saw that bootneuter screen. My phone still works fine and I have an at&t signal. So I dont know if I should not have seen that screen at all. But for sure, uncheck activate phone under general tab and uncheck unlock baseband under bootneuter.
4. I selected cydia installer and installer 4 under cydia packages and custom packages.
5. under custom images, i deselected both images to keep the originals. you can keep those images or select others if you have some downloaded.
6.then clicked build.
7. I downloaded the baseband files but did not need them.
8. saved the custom fw and let pwnagetool build the file.
9. I hit no on has my phone been pwned before.
10. successfully put into DFU mode the first time. I followed the on screen directions and timers and it worked flawless.
11. closed pwnagetool. itunes recognizes phone in recovery mode. then make sure that you shift+click on restore or option+click on restore to search for the custom restore file that pwnagetool created. probably on your desktop.
12. after itunes finished, i set it up as a new phone. i still had all my contacts and calendars and stuff since I backed it up before i started. like i said before, after itunes finished and the phone started the first time, it gave me the bootneuter screen. it said flashing baseband and flashing bootloader. I dont know what it did but I still have an at&t signal. so i hope that it did not mess me up.
13. then i proceeded to set my phone up like normal. had problems with visual voicemail. searched on here but couldn't find the answer i liked. so i just hit visual voicemail button, let it dial the number for a minute and the vvmail password popped up (which is want i wanted) so i entered in my password and my saved voicemails popped up like clockwork.
my youtube is working great. locate me working great. maps working great. cydia and appstore working great. downloaded and installed programs from both. set up my mail and everything else. so far everything is working fine.
I was surprised how long all this took from starting (dling fw 2.0.1) and finishing(dling programs off cydia and appstore). only took about a couple hours.
I am Pwned on fw 2.0.1 and everything is working great! I hope that maybe this will help someone. Any questions, feel free to ask. Like I said, I am by no means an expert.