The technology exists to solve the cube in any way possible.
I.E., tools exists to do the most primitive of operations to
individual cubies (rotating corners, flipping edges, moving three
corners around, and moveing trhee edges around). Using these, any
method of solving is possible (even solving a corner, then the
edges around that corner, then the corners around those edges,
etc, all the way toward the other corner). Since everybody tends
to develop their own technology, they develop their own favorite
way of solving.
Personally, at present, I solve
the top edges
three of the top corners
three of the middle edges
the last top edge
Up until here the algorithms are quite simple and now I only have
the bottom and one middle edge, which I solve in whatever way
looks most promising. Using this sequence, I am consistently on
the order of three minutes (tending toward 2.5 as I get more
familiar with the method)
Intuitively, I believe that God's algorithm is less than 35 or
so, and I would not be surprised if it is less than 30. Under 25
would really surprise me.