Information once available only at the FBO or, more recently, from a home computer is now available to pilots in flight. For VHF datalink services, ground antennas must be deployed abundantly in order to provide appropriate coverage. For providers using satellites, maintaining satellites and their communications technology is very expensive. With a leaner, scaled down approach targeted at providing services to the masses, the company is hoping to avoid costly mistakes made by competitors like Iridium. As for bandwidth issues, beaming large graphic files aboard airplanes isn't exactly easy whether you're using a satellite or ground-based antenna.
Frequency plays a large part in how much information can be sent and received at one time.
Think of it like trying to squeeze a big file through Internet lines. Download times are effected by how large the file is and what type of service you have. The very low frequencies are slower but have better range, much like regular phone lines. The higher frequencies can transmit more data but are limited on range, similar to the fairly speedy DSL or cable line. An FAA report indicates that in the near future there will be sufficient capacity to broadcast 30 different graphical weather maps every five minutes over a dedicated VHF channel.