i would definitely do a clean install if i felt i had been installing a load of crap that had probably left stuff behind (browser plugins, kexts, prefpanes, input managers etc) and some apps will leave stuff behind if you just drag and drop them to the trash.. it can help get rid of stuff you might of forgotten. i even had some ppc stuff running in rosetta as launch at startup background processes that i didnt realise was left over in my old install!!
if you have been careful about what you installed though there really is no point. although like i said if you put your data on a different partition it doesnt even matter
if you have been careful about what you installed though there really is no point. although like i said if you put your data on a different partition it doesnt even matter