I have a friend who had around 2000 visitors per day to his website before webdesigner with no SEO knowledge changed all his urls. Ive used the wayback machine and google analytics to determine the old urls and I've done a 301 redirect and checked that it redirects properly.
My question is how long does it take before Google notices the redirects and passes link juice? And will those long lost backlinks who where pointing to 404 pages count in Google Webmaster Tools, I mean will I see a higher number of backlinks?
And last question, will I get a higher PageRank?