Hi ab2013,
I'd say it really, really depends on where you are applying to. What is considered a good score varies a lot between different universities, and even between MS and PhD applications. E.g. a professor at a top-20 university told me that the lower threshold to aim for for their programme was 85th percentile. Less competitive programmes likely have vastly different expectations (but, of course, few of them publish any information on that topic online). I'd say if you're in doubt, try giving the graduate administrator at the department you're applying to a call, and ask what kind of scores they are usually getting from successful applicants - they might be more willing to share this kind of information over the phone than on their website.
All that being said, if I've read the PDF on ETS's website correctly, a 700 score translates to 47th percentile. My gut feeling is that this is likely not going to help your applications for most programmes (but again, if in doubt ask them).