My understanding is that apple's MOV offers much more standardized
selections of codecs than AVI does. Individuals may use some obsolete codecs
and package the whole thing as an AVI, which gives editing programs a lot
of trouble.
You don't have to have Quicktime to play MOV files. Some third-party
programs like VLCplayer can do it too because it comes with all the codecs
necessary to play MOVs.
Most pro-level editing programs (FCP, Premiere) has nice compatibility with
MOVs. Using AVIs is always