I agree with Neil. However, I might point something else to consider. I'll use an analogy- just 'cause....
I once heard a story about Jack Nickelson. When he was young and undiscovered, he did a screen test for one of the large movie studios. After viewing his test, they said, "We don't need you, but if we did, we would need you real bad".
Studios may not use a lot of Houdini artists, but when they need them, it is usally for a strong reason. Although there are more Maya jobs, there are also many, many more artists looking for Maya work. There is a good chance the supply of Houdini artists has not saturated the jobs available. So while the Maya jobs are picked clean by the masses, a Houdini artist might be able to walk right into a job because there aren't as many people that know Houdini.
If you disagree, consider the value of UNIX righ now in the information world. There are a lot more jobs for system people on the Windows platform, but everyone knows this platform know, and can get trained anywhere. Yet, those with UNIX experience can get a job easily, even without much experience. Those with experience can make a killing.
I'm not saying to switch products, just don't assume you have no other options.
Just my 2 cents worth.
Urp