Pros
Interesting work with the latest open source technologies. Small company so you can make a difference and shape what's being done - more satisfying than being a small cog in a big wheel somewhere else. Suggestions like new software or better ways of working are taken on board by managers so you can really help influence whats happening around you. People are generally good, and from what I see there's not much politics or people playing the game by putting others down. Salaries that I know of are at or moderately above market rate. Working hours are fine and there's good work/life balance. Management is good at allowing early/late starts and occasional working from home. Social life is good and its the first place I've worked with a beer fridge :) Office is in a good, very central location, handy for Dart and Dublin Bikes
Cons
It's a small international company so top-level management seem to travel a lot - limiting the time they are available to actually lead or manage. Communications aren't great in this regard and teams can get mis-aligned. As company is growing, most new roles have been hired in, only bigger teams seem to have promotion prospects and that's pretty rare - so you need to be happy with the role and salary you start in. Other benefits are thin on the ground - no pension or health contributions.