Which one uses less megabytes per hour of internet to use out of MSN and Facebook?

[ben f]

My girlfriend doesn't have wireless or anything for internet, thus she uses an internet dongle. To save using internet I was wondering which one out of Facebook Chat or MSN messenger uses less internet downloading when chatting? Just normal chat, no video calling or anything.....

[DashyFTW]

I would say Facebook uses less Internet usage. Since MSN that I know of has many advertisements and visual enhancements. Remember, the more things that are going on on a site the more internet usage is required to constantly update it.