What programming language to use?
MoeDrippins: The biggies have been mentioned.  Ruby/Rails has a very fast time-to-market, but suffers runtime performance issues.  However, it might very well be "fast enough" for what you want to do.Python has a screaming gajillion well written and supported libraries, and the language itself is very...orderly.  That  suits some people very well, and others is an anathema.A new one on the block is Scala and /Lift/.  Probably not as mature as either of the above, but runs on the JVM so you can stick it on Tomcat or any other java web container, and as such you have a lot of hosting opportunities.