Am I missing something or are Apple shipping almost unusable
configurations?

Does the increased processor power in current Macs make THAT much
difference to make up for the shockingly low amount of RAM?

I didn't think OS/X was usable with less than 512MB.

Andy Dent BSc  MACS  AACM   http://www.oofile.com.au/
OOFILE - Database, Reports, Graphs, GUI for c++ on Mac, Unix & Windows
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