Part V of the 990 is "List of Officers, Directors, Trustees, and Key Employees"; Part IV of the 990EZ is "List of Officers, Directors, Trustees, and Key Employees." I honestly don't see the point of creating more paperwork by filing anything else with the IRS.
You can just send a letter listing your new officers to the IRS each year. In fact, I dont' think the 990 even asks for a list of current officers. Call the IRS and ask for the mailing address; we didn't use a standard form, jsut a letter.
Every year when you file your tax return you have to provide a list of all the new officers, so that suffices as notice to the IRS. There was someone on here a long time ago who had found a form number that you could file whenever you have a change of officers, but I can't find that post, and I've never known anyone to actually do that.
One of my board members asked if we had to keep ammending our 501(c)(3) each time we elect new officers. Do we have to do that? I did check the box asking for exemtion not to have to file the 990's (I think)