Do you think you could have done better? If yes then retake it. If no then move on to other aspects of the application.
That being said, how are the other aspects (GPA, work experience, community service) of your application? Because if you think about it, in its very essence, 690 still has a 6 in its hundreds digit, but a 690 already puts you in the 90th percentile.
Also, I heard that some top-tier companies require MBA graduates to have a GMAT of 700 and above. I heard McKinsey and Barclays Capital require graduates to have a GMAT of at least 700. Hope other gmatclubbers could chime in on this.
Far better is it to dare mighty things, to win glorious triumphs, even though checkered by failure... than to rank with those poor spirits who neither enjoy nor suffer much, because they live in a gray twilight that knows not victory nor defeat.
- T. Roosevelt