Hello,
I have installed VZ in Home Agent, and I have noticed that my startup times significantly increased (Vista). Instead of goin to normal desktop, my PC goes to black screen and stays for about 1 min. Even after uninstalation of VZ agent such behavior persisted. Finally I had manage to find that it is some service called IHA_MessageCenter (or something like that, I have already uninstalled it so the name may be slightly different). As I understand this service is installed together with the home agent, but for whatever reason is not uninstalled.
This service took very long time to start and to communicate with internet. After removing the service everything become normal.
Anyway, I thin VZ could have done better job with both making this service not to slow down the startup and with service being uninstalled together with agent. It took me several hours to find the reason and to fix it. What a loss of time...