Ask HN: Your use of Linux for Server Infrastructure?

My organization runs and manages a mature Web property that has standardized on CentOS 5.x for all our infrastructure. We host most of our servers on EC2 but also use 1000Tb.com and ServerBeach.

My question to the community is this: what Linux distributions are you running on and why did you chose that distribution? Is it ability to maintain? skills? bugs? performance? other?

For us, the critical applications we run on CentOS include:

* haproxy

* Apache bundled with CentOS

* MySQL bundled with CentOS

* MongoDB (via their yum repositories)

* PHP 5.3 via http://www.webtatic.com/packages/php53

* Icecast (mp3 broadcast streaming server)

The reason why I ask this is, well, I'd love to hear some lessons learned from folks in the HN community that have had to make this decision. We settled on CentOS about 7 years ago due to my background in the enterprise space (IBM).

Anyways, I would love to hear what distribution your organization is running for your Linux infrastructure, and why.

Thanks!