Geezeo chose Amazon Web Services (AWS) to host their servers because it is cost effective, flexible, reliable, and secure. They currently run 12 servers through AWS for around $900 per month. This allows them to easily scale their infrastructure and try new configurations. In the past, Geezeo had performance issues with an off-site database, but now run an application server, harvest server, and database cluster on AWS with regular backups to S3. In the future, they plan to add more application servers and implement a MySQL database cluster for improved performance and scalability.