Last week I wrote about whether Google’s potential acquisitions might be stifled by its focus on its own infrastructure software projects but noted that by releasing App Engine the company was encouraging a wider ecosystem of applications based on its platform.

What I didn’t discuss at the time was the potential risk of application vendors finding themselves locked-in to the App Engine platform. Of course Amazon also has this issue, the potential impact of which was revealed this weekend.

It is with this in mind that it was interesting to see the debut of 10gen, a new open source cloud computing start-up founded by Doubleclick veterans and backed by Union Square Ventures.

Over at The 451 Group’s Cloud Cover blog, Vishy Venugopalan has the details:

“10gen offers an open source stack consisting of an app server and object database; developers can write apps in server-side Javascript or Ruby (experimental) and host it on their own computing clouds,” he writes.

“It’s also striking that many platform-as-a-service companies deviate from the standard Web server-app server-relational DB trio, of which the LAMP stack is an example. Google App Engine uses BigTable for its storage whereas 10gen wrote its own MongoDB database.”

10gen also has it own application server and file system, and the whole lot is available under open source licenses.

Of course 10gen isn’t the only open source cloud enabler/provider. There’s also Enomalism and Joyent among others that boast their ability to reduce vendor lock-in. Then there’s the likes of Eucalyptus, Puppet, Hypertable, Hbase, and Hadoop.

While Amazon and Google have first mover advantage when it comes to the cloud, could concerns over lock-in and portability mean that open standards and open source are the long-term platform for cloud computing?