Is bass guitar the new lead guitar?

I've spent a while in the last couple of days here at PA looking through the old and new versions of the Rogues Gallery (which is, may I say, the most successful thread started by lil' ol' me). Many of you post pictures posing with, or playing your favorite musical instruments (fair enough, I'd post one of me with my Hammond if I had such a piccie) - and I noticed a trend...

A majority seem to be bass guitars.

When I was in my teens, there were of course many of us who had/played instruments, but a vast majority were lead guitars - nobody wanted to play bass guitar...

OK, the 1970s was the time of the guitar hero, but there are just as many (arguably more) great players now as there were then; conversely, although the bass guitarist has come more to the fore in recent years (especially in certain areas of prog), we had outstanding players back in the 1970's, too (ah - the 1970s, when bass guitars only had 4 strings...).

So - is it just my perception, or has the bass guitar overtaken the lead guitar as the instrument of choice, and if so, why?

...and for a bonus point, why are bass guitarists now unsatisfied with 4 strings, and prefer the 5 & 6 string versions - and don't give me the "they're more versatile" argument before listening to 4 string players like Jaco Pastorius, Jeff Berlin, Dave Holland, Geddy Lee et al.