The Huffington Post (of all places) has put together a rather incredible look at the early history of Siri, and it turns out that Siri almost ended up being a built-in feature on all of Verizon’s Android phones, until Apple swooped in and bought the whole thing out.
According to the report by Bianca Bosker, just months before Apple acquired the company, Verizon signed a deal to make it a default app on all Verizon smartphones. Given that most carrier-installed apps are famously mediocre, I can only imagine that something like Siri would either have been a revelation, or somehow made unusable.
However, Apple bought the company, and demanded exclusivity.
Some other interesting tidbits from the article include that Siri was born out of a Department of Defense AI project, and could originally connect to 42 different web services, which Apple pared down.
The whole article is a great read, if you have the time.