Sources Say Apple Originally Planned AMD Chip For MacBook Air
Several media sources (here's PC Magazine's version), all seemingly based on an account at SemiAccurate citing (but not naming) "multiple sources," report that Apple originally planned an AMD-chip based MacBook Air, rather than the Intel-based version that emerged later ("Plan B," says the report).
I'm not sure why you think this, if they were looking for power consumption, wouldn't they go with the Atom?
Only an imbecile would put an Atom processor into a laptop. Performance is about a factor five less than what is in the slowest current MacBook Air. Atom is only for toy netbooks.