It's interesting that Blekko was in development for over three years before launching. Granted, it's a search engine, but the world has changed an awful lot in those three years.We felt that the threshold for a "minimum viable product" in the search space was higher than for other products, because the expectations are so high. Negative reception on launch day tends to set a permanent impression in the market which is difficult to recover from, as Cuil found.
In part this is because search engine launches tend to get more attention than launches in other product categories.
On one hand, people have told us we're crazy to be even trying to take on web search because it's impossible... On the other hand they ask why it took us so long. ;)
For our previous company, Topix, we soft-launched a prototype after 9 months of development, and then followed up 3 months later with a bigger press launch. We could do that with Topix, but I don't think it would have worked with blekko.
Some of the dings we've gotten in the launch press actually seem pretty reasonable if you consider that we have a 10-day-old web search engine being compared against ... Google.
Two weeks post-launch, we have a bunch of fans, are getting sustained search traffic 24/7, have users creating slashtags, bloggers are writing how-to posts and guides to using blekko, and we are receiving tons of great feedback from our initial surge of users.
So maybe we launched the Minimum Viable Product after all.