mcskoufis - 5:44 am on Sep 4, 2010 (gmt 0)

The last site I worked on and had a major restructuring of URLs, content and navigation took about 6-8 months to see some of the old traffic back and some new rankings in Google.

Since I wasn't seeing any positive results after 4 months I started getting links from some authoritative sources and I feel that it is likely this boosted the site and not that the "sandbox" filter was taken off...

Also something which may or may not be the case with your site is the fact that the new restructuring reduced the URLs in Google's index by nearly 100,000 (duplicate) URLs, which I suspect is what caused the site to stay in the "sandbox" for so long.