If you include your GMAT score on your resume, companies will take it into consideration. But you don't have to disclose your score.
Your GMAT score isn't as important of a factor as your GPA. With respect to GPA, there is a cut-off; resumes with a GPA lower than the cut-off are automatically filtered out. I haven't heard of a cut-off for the GMAT, however (or even a requirement). GMAT is used as an entrance exam for business school (not jobs), whereas GPA reflects your entire performance during school. I therefore don't think companies put too much stock into the GMAT. After all, your MBA / education and the institution you went to are what matters. If you bombed the GMAT, but went to a great school, you would have effectively disproved your score. On the other hand, if you aced the GMAT, but went to a less than stellar school, your score would unfortunately not reflect your education.
Ultimately, your two years of education > a test you took in a couple of hours.
I personally think a 700 is more than adequate for companies (if they are indeed looking), and I wouldn't waste my time re-taking.