One thing also to mention - ensure you're not running any other downloads at the same time - if you've got anything running in the background that's downloading actively or parties in the house partaking in heavy p2p activity, then this will affect your download rate.
If you're all good on the bandwidth (and your ISP doesn't suck - I see you got 10mbps on the test?) then try restarting steam (it can screw up occasionally I find). If it still doesn't go fast, then yeah, prodding your computer/router is advised. You may wish to tell us your ISP to see if us forumgoes know anything about it.
Also check if your ISP is liable to throttling Steam traffic. I've heard some ISPs in other countries host their own Steam server so that people can download off that, and not the main ones, so that certain net traffic can be molested with, without upsetting the Steam users.