its like a place where google put the banned website. website inserted to sandbox is not seo friendly. but keep doing unique content, you will be release in about 1 or 2 month perhaps.
When google removes a site from its radar, giving it no place in its serps... it is called sandboxed. It is akin to being temporarily penalized or banned! Hope the article on Wikipedia for the same will throw more light on it for you... SANDBOX! Regards, RightMan
if you will do the Black hat SEO i.e unlimited submission than Google will send your site to Google sandbox.
this definition for Google sandbox effect in SEO from my E-marketing glossary which provides succinct definitions of the many terms related to managing and implementing Internet marketing today.
If your not dot your site in google in backlink, on google if your pages not display that means your site in Sendbox
so many differernt answers and all different to the stickied post "Google Sandbox FAQ" http://forums.digitalpoint.com/showthread.php?t=71522