12bar,
I had my right hip replaced in 1998 and my left hip in 2008 (at 62). It is not minor surgery, but it is very routine and most people get dramatic relief from pain and stiffness. Other than being conscious of the range of motion limitations (which fade with time), I have no restrictions on my physical activities. I ride as often as possible, play tennis occasionally and may snow ski next winter.
Within a month or two following hip replacement, most people say "it doesn't hurt anymore" and "I should have had it done a long time ago".