It would be neat but its very unlikely. I don't know much about webOS but I do know alot about computer and using what i know between the two I know that WebOS is based off of linux but Mac OS is based off of unix and Mac and unix are pretty much nothing alike which makes MacOS nearly impossible to work with, and I'm thinking WebOS is the same way so that doesn't help us at all (android is based off of linux), WebOS also only works on certain Qualcom processors which im almost sure the processor in our phone is not one of the few supported ones and if it did work with our phones processors we'd need the source code which would be very hard to get because it is not an open source like android is, and someone would have to develop a kernal that it would run with which would be very difficult.
The way I see it it'd be alot like porting the iPhone OS onto our phones which we already discussed a few weeks ago when someone else asked about it.