As of the latest 18.104.22.168 out in June 2010 the setup seems to run unattended with the above changes, however it ignores the flags themselves and installs the items you set to checked=n regardless.
To get around this, modify the InstSrc and InstParms in each section you want to exclude to run simply the postproc.exe file.
Also, for a completely unattended install without next/launch buttons, you need to kill the Aim.exe task before running setup.exe (taskkill /IM aim.exe /f will do this, or a third party app will as well). Your deployment method may allow for detecting the launch button at the end, but if not you can modify the setup.ini file itself to run the taskkill as the last task.
The below modifications are what I've done for a completely unattended install without setting the home page to AOL, without AOL search, and without AOL toolbar:
SelectProd=This was the section to set AOL Search now just runs postproc (which does nothing)
SelectProd=This was the section to set home page now just runs postproc (which does nothing). you could change instsrc back to bsetutil and instparm to: -target default -homepage http://cnn.com though for example
The setup program requires taskkill or whatever program you're using to be present in the current directory. Using a full path such as c:\windows\system32\taskkill.exe will not work. If the .exe is not present the setup will immediately fail. I've tested XP's SP3 version of taskkill with Win7 64 and Vista 32 and it works successfully to do this job in those. You could use pskill.exe instead, but the newest versions from Microsoft present the user with a EULA that they must click. There is a /accepteula 0 flag but that does not seem to be compatible with this installer. I used an older version pskill 1.11 successfully without the EULA issue.
If you choose not to terminate the task and present the user with the 'close'/'launch' dialog at the end, AIM will startup under whatever privileged user you're running the install as. This presents a security issue because AIM will startup Internet Explorer as the same privileged user, giving the end user full access to the machine.
* For future versions yet to be released: the checked=n selectable=n items are ignored in the current version of setup, though this seems like a bug. If AOL changes this in later versions, the above will most likely still work fine as far as not installing the unwanted items, but this will also mean the taskkill termination section in the IETOOLBAR would be skipped, so you would have to find a new way to do that. (perhaps setting checked=y will make it run it again in the future version, but who knows if that will still be an unattended install then)
Just a note I wanted to share. If you use an IM logging system which requires you to change the host address or port information you need to make the change you want on a test machine. Then go to the logged on user's profile under local settings\application data\AIM\Settings folder and you will find a global.xml file. This settings file is created on first run (if it doesnt already exist). This is the file which contains the connection settings. What I did was copy this xml file and did a post action to copy it to the directory on install.
This is a per user file so for each user profile on the machine this would need to be set. I'm not sure why AOL would have chosen to set this as a per user setting rather than a per machine setting.