Updating from 10 5 8 to 10 6
Updating from 10 5 8 to 10 6 - Adult Chat Rooms
Some things won't be compatible, but all of the mainstream programs have either released new versions that are fully compatible or the programs work fine anyways under Snow Leopard.99% of the Applications aren't even "installed." They are simply downloaded and copied.
A few apps and some low-level things like prefpanes and extensions needed some tweaking, usually by upgrading to SL-compatible version.I followed snowleopard.for a while until I was comfortable that my gotta-have software was compatible (or there was a SL-compatible version) before I made the jump.I downloaded the 10.6.2 combo update before I did the OS update and applied it immediately after the update finished.I'm happy with the results on 2 i Macs and a Macbook.There are two major things which can go wrong and which are rather common among OS X users.That isn't necessary, but some people believe that it is safer to do that with major upgrades.
I have never had to do that, and it's overkill in most cases.
With Mac OS X, there are three ways to install the OS.
1) Some older versions of Parallels are not compatible and an upgrade to a compatible version is not included in the license.
(At least that was the case some months ago.) 2) Macports and quite possibly all other ‘low level’ installation packs should be completely reinstalled.
Most other software should have already nagged you with the installation of a new version that should be compatible.
Just to be clear here, your question implies that you are wiping our your old 10.5 system, reformating the drive, and then installing Snow Leopard.