[Update #2]: Guild Wars 2 will be greatly improving the colossal world bosses with the July 19th update.
[Update]: The Guild Wars 2 team is working on addressing the rather poorly received balance changes.
In order to sort out some of the balance problems that have appeared alongside the End of Dragons expansion, as well as to reshuffle which classes have access to some of the all-powerful stat buffs, Guild Wars 2 has now unleashed a sizable balance update. Unfortunately, as is often tradition with Guild Wars 2, the changes are all over the place.
Some classes like the Engineer and Guardian have gotten through the update with barely a scratch, despite being some of the most popular and powerful in end-game scenarios. On the other hand, Warriors and Elementalists have received some sizable nerfs that will likely mandate a follow-up patch in order to get the two classes back into shape.
The good news is that ArenaNet, following a massive outcry from the community, has already started working on a new update that will hopefully address some of the freshly introduced problems. So while the Warrior banners may be incredibly annoying to use right now, there's still a chance things will pan out well over the next few weeks.
Whatever the case may be, I'll make sure to let you know. Until then, however, you can learn more about the recent update over at the Guild Wars 2 website.
Have fun, and if you haven't tried one already, this would be the perfect time to take the Mechanist for a spin. The specialization is currently absurdly powerful and can roll through most content with little effort, so I'd highly recommend indulging in it before things get toned down.