I have bought a better domain more fit for my business but my present domain has Alot of top 10 rankings that i dont want to loose on Google, Yahoo, etc. If i do a 301 redirect from olddomain.com to newdomain.com , its my understanding that thru webmaster tools i can advise google of my new domain. How soon does the change take effect? Does it cause an loss in Positions? and How do I handle the change as far as Yahoo goes?
If the keyword you have targeted are competitive. Then yes your SERP will be effected. This has happened with my blog.
your current ranking may be affected. i would suggest that make another website for your business with new domain and optimize that website. you will get better business.
If you redirect from old to new domain, its certain that your website's SERPs positioning would effect badly. You have done link building for your old domain, so only 301 redirecting not gonna help to maintain your SERPs. If you can, you inform other sites admin whoever given link back to your old site, and ask them to link back to your new domain instead old one. At first there would be a huge downfall but later it will definitely improve. Thats a solution if you really want to change the domain. But I suggest you not to redirect. Let your old site be in its position as askyseo said and create new website with better info. and features. I am this will certainly beat your old domain . Best of luck
From experience, you'll have to start from scratch with the new domain, moving information over will just cause issues with duplicate content and dead links etc. If you've already got some top 10 rankings and you want to keep them why not 301 the new domain to the old domain?
Why do you just need a new domain? If it is more beautiful, make a redirect from it to the old domain.