[Quick micro-post just to get back into the habit of updating this dev blog :P ]
Roughly 7 or so months ago, I knew jack squat about maven. Fast forward to today, and I'm quickly finding myself turning into a fan boy. I hate fanboyism in general, so this fact disturbs me. But I've liked everything so far with maven in comparison to the other tools I've used (namely ant/make for java related projects/systems). In fact, a colleague of mine and myself are looking to move all of our projects over in order to standardize our engineering group on a single build system - with only 2 out of 5 projects potentially requiring legwork.
IRC, message board, and news site chatter tends to be very anti-maven - and some of it is perhaps justified. Maven is one of those things that should automagically work when done right, but requires taking a leap of faith, releasing control, and allowing your project to adhere to some seemingly arbitrary standards. So to those control freaks still operating with ant/make, it'll seem like a bit of a step backwards - especially when it doesn't work.
But ultimately, the end result of using maven is that all of your projects will be structured the same, adding new things to your build that aren't completely wacky (read: may require a plugin) may result in, at most, a new dependency to your pom. I find this critical, as I've seen new people coming on board on our non-maven projects experiencing a large ramp up time with the build systems there.
So in short, I'm currently a big maven fan. I'm starting to read Maven - The Definitive Guide to further my knowledge about it. But, as with most things in the honeymoon phase, let's see how I feel about maven in another 6 months after a few project conversions.