I'm sure Russ will chime in at some point to correct whatever I get wrong, but...
Many of the same leaf types are used in both pipe and cigarette tobacco. Most cigarettes are primarily Virginia, Burely and Oriental, just as in pipe tobacco. As far as the quality, there are certainly a multitude of grades for each leaf type, and I'm sure you'd find both high and low grades in various pipe and cigarette brands.
A couple of key ingredients found in most machine made cigarettes are not found in any traditional pipe tobacco that I am aware of: Recon and Expanded. Recon is basically tobacco dust that has been turned into a sort of paper. Recon is still, technically, tobacco, and far, far cheaper than leaf tobacco. It is basically used as just a cheap filler.
Expanded is tobacco that has been freeze dried then super heated, which vastly increases the surface area of the tobacco. Expanded is actually more expensive than regular tobacco, but because of its fill value, it can still reduce the manufacturing costs of a cigarette. Many machine made cigarettes contain as much as 40%-60% recon and expanded tobaccos.
Cigar wrapper, filler and binder leaves are a different variety than what is used in most pipe tobacco blends. Much is what I've heard referred to as 'dark leaf' tobacco.