bwnbwn - 12:21 pm on Apr 5, 2012 (gmt 0)
I doubt the change you did is the problem, what probably happened is he has removed some links he had pointing at the site. It is hard to tell you what's going on without looking the site over and doing some research. I would join WM (I get zit from this IMO if is money well spent, been a member sine 2005 probably stay a member till a cow lands on the moon), go into the review website section. Do as best you can to offer some good points to a couple other sites in review and then submit your site. You will have the top guys in the industry pick over your site and point you in the right direction.
I myself try to teach SEO best pratices to my clients so when they decide to take it over their not in the dark on were the site is and what has been done. Not knowing you had a blog on your own site tells me it really needs to be looked over in detail.