Hi aashigarg,
Since you have not been taking CATs/mocks at regular intervals, it's tough to say what your actual 'ability level' is right now (although there is a reasonable chance that it's in the low-600s to mid-600s). Since it's been 2 weeks since you took your last CAT, I suggest that you take a NEW CAT sometime soon (and you might consider taking one of the Official GMAC CATs from
www.mba.com). Make sure to take it in a realistic fashion that matches-up with what you will face when you take the Official GMAT (take the FULL CAT - with the Essay and IR sections, at the same time of day as when you'll take the Official GMAT, if you will be at a Test Facility, then wear a face mask, etc.). Once you have that Score, you should post back here (or you can feel free to PM me directly) and we can discuss the results and how you might best proceed with your studies.
Statistically-speaking, raising a low-600s Score to the point that you can consistently score 700+ will likely require at least another 1 - 1.5 months of consistent, guided study - and you'll likely have to make improvements to how you handle BOTH the Quant and Verbal sections. Thankfully, the GMAT is a consistent, predictable Exam, so you CAN train to score at a higher level. With a December 29th Test Date, you only have about 3 weeks of study time though, so you might want to consider pushing back your Test Date.
1) What are the exact application deadlines that you are facing in January?
2) Going forward, how many hours do you think you can consistently study each week?
GMAT assassins aren't born, they're made,
Rich