If you are targeting instant traffic at your website then PPC is the best option but if you have patience and wait for visitors after long wait then SEO is good. If you are expert in optimizing your website by using white hat SEO then I will suggest you to go the SEO because PPC campaign is costlier but SEO does not need more investment.
For me, i give my vote on SEO. Although PPC gives faster results, you have to spend some money to have the results you wanted. While with SEO, you will get your backlinks without spending a dime. Work and effort to achieved long term results. This is just how I see the difference of the two and anyone can object.
Though PPC shows instant results but it is just a temporary solution whereas SEO no doubt take little time but it makes sure that once it is on top nothing happens to it for a longer period. I prefer SEO then PPC. Anyways PPC for a new site will be little cumbersome also.
PPC and SEO both play an important role in Internet marketing. If you have enough budget to run campaigns and want instant results then PPC is best option. But when we talk in terms of money and long lasting results then SEO is the better option.