The Angstrom Linux used in the Beagle Bone is under a lot of development and maintenance. Depending on what release came with your board, you may eligible for a large number of updates. My first board came with an older release of Angstrom Linux, and it took between one and two hours to finish the "opkg upgrade". Even then, there was not enough space to hold all of the updates available, and I got a message stating "Do you need to run opkg udate?" So I did another "opkg update", followed by another "opkg upgrade", and was able to finish getting all the updates. I try running the update cycle every now and then. Sometimes there are no updates, sometimes there are, but they have never taken as long as the first time. I'm just pleased that folks are enhancing Angstrom Linux, and that I can get the updates for free.
As for the wifi installation, I haven't been able to get it to work yet. I see other messages on this forum about the same problem.