said by BobbytheBrain :
Maybe nobody uses it because the interface was designed by idiots.
Bingo! The fact Joost -IS- an application in the first place is one of their biggest faults. It looks four years old at a time when everyone else is moving to embedded web video which requires little on the part of the viewer to get the content. Joost requires a horrendously resource hungry application to be downloaded and installed before you even get started, and that's a major downside for a lot of folks who simply are not going to bother.
And when you do get it installed, the CPU and memory load of this thing is astonishing. I can barely get it running on my two year old laptop because it is so resource hungry (and demands a contemporary videocard with enough memory on board for a reasonable experience) it essentially slows the computer to a crawl.
The client's look and feel is completely non-intuitive, looks old-school, and the content menu is done with oversized square boxes with show logos that you need to wade through to locate a show you're interested in.
The entire delivery system is, as others have noted, BitTorrent based, so it will also suck your Internet connection (never, ever leave the thing running in the system tray - you simply stay connected to help deliver their content to others, eating your bandwidth).
And, most annoying of all, no effort is really made to inject advertising in an appropriate manner. In many cases, it's the same 15 or 30 second spot run at every ad break (usually at a volume many times louder than the content you are watching, blowing you out of the room).
The claims that broadband bandwidth is the problem for Joost is a joke. The real problem for investors in this mess is that their deployment using a software based application is behind the times, not well coded, and in light of launches like Hulu and other web-based video applications, threatens their viability.
Add to that the concept of metered broadband traffic, where an application like Joost could blow through your monthly allotment delivering content to other people 24/7 if you leave the thing running in the system tray, and Joost becomes as relevant as other yesterday technology like Limewire.
Time for them to rethink things from the ground up.