The one issue with going bigger and better with my Tweet collection is the actual storage, especially if I want to continuously run a spatial DB, like PostGIS. I was just poking around on the Intarwebs and the pricing seems prohibitive for a beginner spatial hacker with significant data.
CartoDB can get you started for $29 a month, but you only have a piddly 50Mb of storage.
According to Heroku, PostGIS is available as an extension to their hosted Postgres product. This includes a whopping 1 Tb of storage. However, the smallest package is $200 a month!
Man, I didn’t know hosting PostGIS was so difficult.