Salesforce.com AppExchange, the app store that lets cloud ISVs hawk their wares on the provider’s PaaS platform, recently hit 1 million installs. And to celebrate, Salesforce is offering some insight into the history of the AppExchange marketplace in the form of a blog entry.

AppExchange apparently started as a design on a napkin in 2005. By 2006, Salesforce.com was ready to unleash it on the world, with VerticalResponse as the very first partner app offered. At the time, BusinessWeek called AppExchange “The eBay of business software.” By year’s end, it had hit 26,650 installs.

A year later, Salesforce had released 100 free apps to the marketplace. Then, in 2008, Benioff made a big show of gifting the App Store domain to Apple ahead of that launch. And 2009 saw AppExchange open the door to service partners, with Accenture, Deloitte and Fujitsu listing themselves. The launch of the Salesforce Chatter social network in 2010 brought new social-focused ISVs to the table.

And now, in 2011, Salesforce has hit this 1 million mark. Intriguingly, Salesforce’s infographic offers another highly interesting statistic: Collectively, AppExchange ISVs have raised $1.04 billion in venture capital funding. And on the occasion of hitting this milestone, the AppExchange team took itself out to dinner at McDonalds. (Now that’s living.)

It’s an intriguing number, to be sure. And it goes a long way toward reinforcing the notion that yes, there is room in the cloud market for the smaller developer. But I’d be curious to hear how AppExchange’s numbers match up against the more recent Google Apps Marketplace, which has been experiencing some interesting chatter of its own — not to mention the Microsoft Office 365 marketplace.