On top of getting passed the protection mechanisms Nintendo put in place to stop the most recent batch of mods, the update also adds a few things that even the official hardware does not, such as support for SDHC cards. Currently, the Wii can only use standard density SD cards, making larger sizes not usable. Official support for SDHC is planned down the road.
Many have criticized Nintendo for working against the modding community, but in truth it is an industry-wide problem. Microsoft and Sony have also worked against modders, to the point of lawsuits and shutting down people making a business out of modding.