In-game, FFXI is capped at 7-8 kilobytes per second. PlayOnline Viewer can download updates faster than that though, and patching the game from a fresh install can be several gigabytes.

Wow, a limit that low? Comcast removed their 250 GB/month usage limit they had early this year, in that it hadn't been raised in the past 5 years but internet speeds had increased. I'm on an unlimited use 1 Mbps line, and I use 300+ GB per month. My internet conection runs everything in my house. Just buying games on Steam uses a lot of bandwidth because they are all downloaded. Microsoft updates every week also contribute.