Lorel - 2:36 am on Jul 12, 2006 (gmt 0)

For those of you who set up a 301 redirect and see no improvement in the SERPs after a resonaable amount of time (long enough for Google to index your 301 and time for it to affect the SERPs) then check your site for hijackers by checking every site listed in the inurl:yourdomain.com and intitle:yourdomain.com.

Hijackers only go after top ranking sites so the fact you were ranking well and dropped suddenly it could be the later problem. Actually I would advise doing both at once. There are so many ways to hijack a site now it's hard to keep up with them all.