Have played guitar for 9 years or so, and occasionally picked up a bass. Until back in spring this year, when I got myself a bass and decided to have a 'proper go at it', mainly because I was taking over bass duties in a band when the bassist was absent (often). Now I think I might prefer bass (playing in the band), and might even suggest dropping the few numbers I pick up a guitar for...
So, a guitarist and hopefully becoming a bassist as well (not a guitarist who "plays a bit of bass"). Certainly enjoy playing both, but in a band context the bass can be more fun.