Most of the time, they are running a free 50GB for life promotion, which is a pretty good deal.
Room for Improvement:
Only web access for non enterprise customers. Come on guys, Dropbox, Google Drive, and SkyDrive all have a syncing feature.The only way to set up a comparable feature is to either:A) Pay for it via an enterprise plan.
B) Set up a WebDAV storage link via a disk mount in your OS (Which is slow as molasses and isn't user friendly at all.
My biggest problem with Box.net is the lack of a free desktop syncing feature. They were the first out of the gate with an Android tablet app and a WebOS tablet app. They were ahead of the game everywhere but where it counted, unfortunately.