Just curious, but do you know why this channel works? Do you know why it is different than official Nintendo channels? Do you know what IOS37 is? If you don't, you can read about it
here.
Honestly, I think you will probably be safe as long as you delete the channel off the Wii before updating to a newer firmware, but I'll wait until the original coders have more of a chance to test various things with IOS37, before I install any of this.
Unless Team Twiizers have misread something on IOS37 (I seriously doubt that), one of two things can happen if you update to a firmware activating IOS37, while having that channel on:
1. The channel will simply not load, and you will be able to easily go into the Wii Settings and delete it off.
2. The installed Homebrew Channel could cause a conflict with the Wii/IOS37/etc., causing it to essentially "brick".
Hopefully, the first thing would be what would happen, but it is possible that the channel could cause it to brick, despite it apparently working fine right now. Also, contrary to what some believe, there are people who don't know what they are doing when installing things like this. If the second possibility were to happen, someone would end up with a bricked Wii.