Yes, many companies will review all their options once they have plenty of capital, and make decisions based on what's best for their situation. For example, Twitter was reported to be switching from Ruby on Rails to PHP or Java amidst all their uptime troubles.
My point is that choice of language is not what will likely stand in your way of becoming a monumental startup success. Yet people will insist on promoting language wars as if it will.
Paul G. has given Lisp a lot of credit for enabling ViaWeb to push out new features in minimal time, compared to competitors who were using languages such as Java. While your choice of language might not be a make-or-break decision, it's good to have all the advantages you can get.
(I think Twitter ended up using Scala, didn't they?)
We could always do an "Ask PG" to clarify, but my understanding of what happened with ViaWeb is you had a group of smart young people innovating on a problem against bulky institutional competitors. When asked who had an offering even close to what they did they said no one. (You might even say they were the first YC modeled company!) Viewed this way I'd say the success was about the people, not the language; they simply used their tool of choice.
I don't know what's the "official" (or real) story on current Twitter architecture.
Right, their success was not purely about the language, I'm just saying it helped (rather, he said it helped). This is drawn from my recollection of reading an article pg wrote. I could find the article if anyone is interested (it is an article about how great lisp is, not specifically the history of ViaWeb, I think).
I agree that some people take the choice of language and architecture a little to seriously. Of course you can start a blockbuster business on PHP and MySQL - people prove that frequently!
Yes, I agree any creator needs an able tool, but that's a clear strength of PHP when it comes to Web deployment. That's a fact. I believe people should use whatever they feel they can get the job done with, even if it's BASIC (http://news.ycombinator.com/item?id=2257866), because focusing on a language more than what it is you're actually trying to accomplish IMO is missing the point.
http://techcrunch.com/2008/05/01/twitter-said-to-be-abandoni...
My point is that choice of language is not what will likely stand in your way of becoming a monumental startup success. Yet people will insist on promoting language wars as if it will.