There are quite a few threads on this...here's some:
I ended up just backing up through iTunes (connect your iPhone or iPad to your computer) and then afterwards doing a system restore (again through iTunes). It took about 2 hours but it is easy and painless. After the restore, everything worked with Match - infact I like the interface and layouts 1000 times better! I also have noticed that when I update my iTunes library and update Match, the new information is almost immediately on my iPhone/iPad now.