A mobile release of Wizard101 would bring in tons of new players, and thus new revenue, for KingsIsle. Due to its turn based nature, implementing the combat system would be much easier than mobile releases of other games such as runescape or CoD.
I know that for me personally if there was a mobile release of Wizard101 I would play a lot more.
A mobile release of Wizard101 would accomplish everything that KingsIsle sought to do with the steam release, but more successfully and with much better results.
I truly believe that investing into cross platform play where players can take Wizard101 on the go would be the best use of any and all KingsIsle resources.