I asked the same thing, and the only answer I got was that there is currently no way. I'm in the same situation, only my Wii is 3.3U.
There was a previous patch to allow access to the Wii Shop after an update, but I don't remember what it was called and I basically hope somebody makes something like that again. Can't wait to see the arcade games! Hopefully the homebrew geniuses will give us the benefit of the new SD Card features without the new firmware.
I'm not totally keen on abandoning homebrew quite yet, not unless they add at least five must-have things. I'm trying to hold out until the homebrew community can make something for playing Doom and other such games on the Wii that actually works. I have NEVER gotten Doom to work. Even with the Homebrew Browser install of Doom, it never works. I do exactly what people in the YouTube videos say and do, but nothing.
Well, you've got a second dude here now. If there's enough people in here, perhaps this'll become a priority and we'll be back in the shop again. Just because I have Homebrew Channel doesn't mean I'm a pirate, but Nintendo sure does want to make it so and prevent themselves from getting money here... >_>