Well according to Serebii.net, the Toys R Us Arceus giveaway ended on Sunday the 15th. It's level 100, is holding the Rowap Berry, and knows Judgement, Roar of Time, Spacial Rend, and Shadow Force. Other than that, nothing major happening other than Pokemon Rumble now available on WiiWare. However, according to Serebii.net's section on Pokemon Platinum, it suggests that the next Wi-Fi event will be a level 5 Jirachi holding a Liechi Berry. This is purely speculation, though, as there haven't been any official announcements made.
However, our friends in Japan now have the opportunity to download a special 10th anniversary Mew. It's level 5 and can only be obtained for either HeartGold or SoulSilver. If you don't have those games, you'll have to wait until late January to download it. Also, for the new WiiWare games now available in Japan, 4 different challenges can be downloaded for the new Mystery Dungeons on WiiWare. These challenges are for Arceus, Dialga, and Giritina. You can also download Palkia and he'll appear in certain dungeons. These are consecutive, however, so they can only be downloaded and will only be available one at a time. The Mew download goes until November 23rd, at which point the Enigma Crystal will be available. This Enigma Crystal gives you access to either Latias or Latios depding on which version of HeartGold and SoulSilver you have. There are also some PokeWaker courses available to download.
For more information, go to http://serebii.net/games/currentevents.shtml
