For amateur photographers or those who can't / don't want to go down an academic route, it does allow for a progression which I found useful. If you already have a degree then it doesn't give you much really, as David suggests, other than another set of letters after your name, and these you have to pay an annual fee to retain (that is in line with other bodies though - I have to pay to keep using CEng after my name in a professional capacity).
I've seen some quite creative work on F panels, but a lot of the L and A work is standard camera club stuff (and I don't mean that in a derogatory way) albeit to a very good technical standard. By and large though it's somewhat different stylistically and subject wise to the kind of work done in colleges and universities. And there's nothing wrong with that as long as you manage your expectations.
If you are a camera club member there are also the PAGB distinctions which may be of interest. Don't know much about them as I'm not in a camera club anymore.