Leosghost - 12:56 am on Apr 27, 2012 (gmt 0)
Fifth - If you live in an apartment block, and one of your neighbors opens a crack den, or something that the cops won't like, or does something the city thinks is dangerous, they may seal off the entry to all of your visitors too..
referring to my recent experience ( reported here ) of having a small group of domains de-indexed by Google, because of what someone else did on their domain on the shared IP I had left those domains on for years..I moved mine to my their own dedi IPs within a few hours of finding that the shared IP was de-indexed..
Instant recovery of all rankings ..:)
The rest of my old co-tenants are still "walled" off , and can't be found..