I use a Visual Studio Setup project to create an installer for some assemblies. However, the fonts the installer uses are always aliased, and don't appear to be the Windows standard.
(Note that the installer text uses aliased text rendering, but the window title uses ClearType)
Is there any way to update the MSI to use ClearType?
Well, the short answer is no.
However you could edit the generated MSI with an editor like Orca which allows to change the fonts families or sizes, but not anything close to enabling ClearType as it is controlled by Windows.
With that said, according to this it seems WIX does support ClearType. Anybody who started with VS installer eventually had their one caveat which made them switch to WIX, NSIS or a commercial solution. Yours might be the most unique motive :)