Jon Ricerca is one of the leading researchers and authors of the Search Engine Ranking Factor (SERF) reports at SearchEngineGeek.com.
This is a hotly debated topic. Some Search Engine Optimizers (SEOs) claim that sites with a static IP address rank higher while other SEOs claim that shared hosting is just fine... that it would be stupid for search engines to penalize shared hosting since we are running out of IP addresses and so many sites are currently using name based hosting. ...I decided to run it through our statistical analysis engine to get the facts. Here is the methodology I used to answer this question. more