You could automate the entire process with a push-button operation. This could be relatively simple too, so you could hire someone to write the code for you.
This is a basic list of what you would need.
1. Bulk (or reseller) account with a provider such as Enom or Dynadot which have API's available.
2. Dedicated server.
3. RSS aggregator or content generator and a collection of templates.
4. Control panel to handle everything.
5. Groups of keywords that you have researched (this part would still take time)
What the steps might look like...
1. In control panel enter the name of a keyword group and submit.
2. System automatically creates a list of possible domains.
3. The system uses the registrar API to attempt to register the domain.
4. Registration process goes down the list of domains until successful.
5. Proper DNS info is set using the DNS servers at the registrar (cuts down propagation time)
5. Successful domain is returned to the system and the site creation process starts.
6. Virtual host is created on the server by the script and Apache is rebooted.
7. Template is chosen randomly and files are copied to the root of the new domains.
8. The system adds either RSS feeds or the auto-content based on the keywords.
I might be missing some steps there. Probably some obvious steps considering how late I am up.
As you can see the entire process can be automated. You could even go beyond that. A lot of hosting providers have API's available which can be used to bring new servers online with your account.
