follow up: Restore point

I'm not sure what it is you're referring to, but if you're asking if Mac OS X has a Restore Point feature like the one in Windows that rolls back OS updates and such, no, it doesn't.

Again, there is no feature comparable to Restore Point in Mac OS X (I'm not aware of any such feature in any UNIX or Linux OS, though I'm by no means fully conversant with all of them). The Restore Point feature is dependent on having some sort of central database of all drivers as with the Windows Registry, and I think most OS developers feel that the Windows Registry model is more problem than having a Restore Point type of feature is worth.

To protect yourself against an upgrade or download causing a system problem, use Time Machine to make a full backup of your system or use one of the cloning tools such as SuperDuper or Carbon Copy Cloner to clone a bootable copy or make a restorable disk image to another storage volume. This is strongly recommended even for Windows; the Restore Point is far from a fully reliable method (I've seen it fail to recover a Windows system from a faulty patch or virus/worm/spyware infestation) on numerous occasions).

A Mac works differently then windows. In windows, through the registry, the os and the programs integrate and the installation of a program changes the registry to the extent that it may effect the os. On a Mac, the OS and the programs are more or less separate so those problems don't occur. Basically, if you install a program and don't like it, remove it. -GDF

You should be fine as long as TM is doing a complete system backup (i.e. you haven't excluded any part of the OS from backup).