A lot can change in a year let alone a couple years. I'm sure when they broke up they had things going on that made them unable to continue but maybe now they've resolved those things and feel they can rededicate themselves to the band.
When you're at this stage in your band's career, getting back together is literally just friends who feel like jamming and playing shows together. It's not like a bit corporate reunion.
If memory serves, they broke up because of personal issues within the band. Or at least that's what they hinted at.
Whatever the case, if they're back together and making new tunes, I'm stoked. I was pretty bummed I never got a chance to see these guys, so hopefully that'll change.