While a good thought, it is not true that more traffic means higher ranks in search. In fact, unless the search engine sends the traffic they will have no idea how much you have. We collect data on clients sites for stats, but no one else knows how much traffic you are getting. It is true, however, that websites that are updated will get more traffic from search. So update frequently with relevant content and the numbers will rise.
A blessing and a curse is that no, search placements are not permanent. When we are competing to get a site higher this is great. Once you get there you do wish that they were set forever. Rankings change on a regular basis with new sites coming online, old sites being well maintained, and a number of other factors. As a general rule, update often to grow and maintain your ranks.
This was once a valid service, but not any more. Today all major search engines will automatically index your site on a regular basis and submitting to them, when possible, is not going to help one bit. Plus, who can name a hundred billion search engines. Normally we are only tracking five. Try it… how many can you name?
Your website is not a Ron Popeil gadget. One day come by and I will show the numbers on a site that is updated frequently and one that is not. Many of you have seen the difference with your own sites when we get a regular update cycle going. Please, please do not set your new website up then neglect updates for months and months.