We're going to start the upgrade to vB4 in about 24 hours. That's a kind of big deal, and for a summary of everything that it means you can check out the thread Archaic posted about the changeover. It means that these forums are going to be down for the duration of the changeover, which will take between one and three days. We'll provide updates as available with more specifics in the shutdown message that you'll see when you try to access these forums at bmgf.bulbagarden.net.
In the meantime, though, you don't have to be bored. We're going to be opening up our vB4 test forum to everyone so you can familiarize yourself with what's coming and have a place to get your BMGf fix. That link will be made available when you visit bmgf.bulbagarden.net upon the takedown. You'll notice that the test forum is a few months out of date; we made a copy of the Bulbagarden database a while ago to use for our own testing, and haven't updated it to the current database. So you'll be missing posts and threads and stuff, but we don't mind if you repost them on the test forum. But remember that the test forum isn't permanent--everything there will get deleted when we re-open the forums you find at bmgf.bulbagarden.net.
You can also access our IRC channel #bulbagarden on irc.systemnet.info throughout the process, or hop on over and make edits on Bulbapedia--both will remain up during the forums transition.
If you have any questions, please feel free to post them in this thread. If you're worried you might forget, don't--we'll provide messages that keep everyone updated throughout the upgrade process right here and on our Twitter account, twitter.com/bulbagarden.
If you have questions or concerns during the downtime, you can reach the staff on Twitter--my handle there is @evklofbulba.
Thanks for using Bulbagarden, and we're looking forward to seeing everyone on the other side of the vB4 upgrade. It has tons of awesome features. We're all excited, and we hope you are too.
evkl and the rest of the Bulbagarden team