Is the new portal backwards-compatible with the previous games?

I know the new Skylanders SWAP Force game comes with a new portal of power, since the old portals supposedly don't support the new SWAP-type figures.

My question is - will I still need to keep my old portal around for the previous games, or can I use the new portal for those as well?

From my experience, the portal of power from SWAP Force is compatible with the previous games for both the PS3 and 3DS version. I will assume it's the same for all console versions.

Theoretically you can use the portal given to you in the new Swap Force Game on the older games. But, if you use the old portal for the newer games, it wouldn't work.