I noticed this morning that the UB versions of Trapcode plug-ins are now available. A quick test with AE CS3 on an 8-core MacPro shows everything working as expected.
Maybe my ADHD is kicking in, but for the life of me, I can't find where the plug-ins are installed. I can't find them in either the application package or the 'plug-ins' folder. Also, I found I needed to manually move the Particular presets into the plug-in folder to make them show up.