Comment Finish, then leave (Score 1) 11
Companies generally react with what's best for the company. You are a company of sorts that supplies IT services to your employer. React in the same manner. I would suggest that what is best for you and your CV is to finish the job, let the software be released, wait a month or two for the dust to settle and then go.
This way you can show that you stayed until completion, that you completed a project successfully and are ready to accept new challenges.
The real question you need to ask yourself is, nevermind the money and the commute, is the work at the new employer more rewarding ? 7K and a shorter commute is nothing when what you are doing sucks hairy loli-pops.
Good Luck!