I prefer not to have my archive anywhere but on my home computer,
I also liked the ability, in messenger 10, to read my message archive if my computer was offline. I realize thats becoming few and far between in todays times but i believe removing the option completely is very inconsiderate for your users. I have downgraded from messenger 11 back to 10 to get back my archive. I reccomend putting the offline archive option back into messenger 11 and allow users to choose between the online/any location access and the offline/1 computer access versions of the message archive.