One has to use what the customer or project requires.
If it is something that we can enjoy, great, if not it is a job and the customer should always be an happy customer.
The same is true for projects: there are relatively few projects that force you to use some particular language.
As people like to endlessly repeat, you should choose the best tool for the job. And, unless there are strong reasons against it, the best tool is one you like.
On a more cynical note: the job market is great right now. If you don't like the technology you're using, it's a prime time to look at new opportunities. Apply to some cool startups doing cool things with cool technologies--at the very least, it'll be exciting :P.
On the corporation consulting world I work, the technology is always part of the RFP sent by the customer to the consulting companies.