Hello Hari,
By looking at Maria'spost,I realized that my previous post was a misunderstanding of your query for Differences between PLM and EAM . However I have a brief answer for your query. According to me at present both are synonyms (Same). May be EAM word is a visionary word to accommodate future evolution of SAP-PM. Possible that to bring CS inclusive feeling it might have been renamed as EAM as hinted by Maria.
Thank you
KJogeswaraRao