There is a certain amount of mystery revolving around oil finishes, with good reason. A good oil finish, while fairly easy to accomplish, is rare to find these days. It's a very low tech process which, when done well, produces a magnificent finish, but it is a time consuming procedure which requires considerably more effort than simply brushing or spraying on a topcoat such as varnish or lacquer. Primarily, an oil finish is IN the outer surface of the wood rather than ON the surface, which is the property that makes it such an attractive finish.
Linseed oil is an oil extracted from flax, and the term 'boiled' is misleading but very important.
Raw linseed oil will never dry, and does not make a good finishing material. Even boiled linseed oil dries quite slowly, and the addition of varnish or driers is common these days to speed drying and provide faster build of the finish. Tung oil has become a somewhat generic term, encompassing many varieties of oil finishes. It's my favorite for the simple reason that it's been around for many, many years, and the manufacturers have in general been quite obstinate about not meddling with the recipe for the stuff, which makes it far more predictable than most finishes. After several years of working with Watco and other oil finishes, it became quite apparent to me that the manufacturers were more interested in promoting and marketing these products with the focus upon 'quick and easy finishing' as opposed to helping the user achieve striking results.