You can easily get compressed episodes of a TV show that are 250MB, so it's like watching a TV series at the rate of 2 episodes every 5 minutes. Obviously better quality is in the range 500MB-1.5GB for a 45-minute episode, so even being generous it's 20 minutes of compressed TV or 70 minutes of uncompressed music every 5 minutes.
Yes, as I understand it, the ~700 MiB "standard" was derived from the capacity of a CD. A rip is definitionally a copy that lacks some of the original data of the source media.
A DVD (single layer) holds about 4.7GB of data.