In light of facebook's acquisition of fb.com from the American Farm Bureau Federation for $8.5 Million
do you think it's advisable, then, for startups to plan to acquire their two-letter equivalents early on at a relatively lower price? For that matter, how many domain names should a startup buy, and what rule of thumb should startups follow when selecting/buying them?
Off-topic, do you think that $8.5 million was a wise use of FB's investment?
Two letter domain names are rare, and (relative to domain prices) very expensive. All of them. The length of the domain name is one of the top criteria for the price of a domain.
Two letter domain names in dot com are referred to as LL.com (for Letter Letter), and I doubt you will find any LL.com for under $50,000.
You can check Sedo.com listing and the cheapest priced is at $99,000.
For Facebook to buy fb.com is really a drop in the ocean. $8.5 million is a huge number for the domain name industry, but is an ridiculously small fraction of Facebook revenues and market value.
So I think it makes sense to do like facebook: first make a billion dollar company, then acquire any domain name you want.