Happy anniversary. For over a decade now, Danbooru has been one of the most important online databases for me.
I must admit I consider Wikipedia more essential for my needs, but... I would give up even Youtube rather than Danbooru if I had to choose. Still images and comic pages just offer me so much more than video clips.
The tagging on Danbooru is unparalleled among the image databases I know, and the quality of the (free!) translations is most often astounding.
If Danbooru as I know it has a major deficiency, that would be the relative scarcity of male-focus illustrations and yaoi comics. Most of the time, that does not disturb me much – but still, more of that stuff would be a plus.
My sincere thanks to everybody who has worked for this awesome site during its existence. Rock, rock on!