Microsoft just opened a link to download Windows 7 Release Candidate (RC), that means the OS passed beta and it should be stable now. You can download the ISO image and product serial number here:

http://www.microsoft.com/windows/windows-7/download.aspx

However, if you have installed the old Windows 7 build 7000 open beta, the RC didn't allow you to upgrade from old pre-released Windows 7 build and it suggest you to make a clean install.

In iPhone OS 3.0 beta, the Settings->General->Nework->Cellular Data Network is empty, so we cannot change any APN settings. So if you have to manually change APN setting, you cannot use any 2G/3G network.

To solve this problem, you can visit this website:

http://unlockit.co.nz

using your iPhone Safari with Wifi. Following the instruction, enter your APN information, and the website will create a profile and installed to you iPhone.

unlockit.co.nz main screen, click "Continue" to edit

Enter your APN settings and click "Create Custom Profile"

The website will create a profile, confirm to install the profile to your iPhone

After installing windows 7 beta, you will see a link at the top right of every windows:

In order to hide this link, we can regedit the following registry:

HKEY_CURRENT_USER\Control Panel\Desktop\FeedbackToolEnabled = 0

Originial value in my Windows is 3.