Two documents have been added to Firebird documentation area
How the cache works in Firebird :
That is based on information Ann Harrison supplied on the firebird-devel list a while back. She has permitted me to document it and make a manual out of it.
And Firebird Internals :

Scott Guthrie recently posted article about New Embedded Database Support with ASP.NET. This made me think about other options, Firebird in particular, and advantages and disadvantages. What I’m going to do is to introduce Firebird Embedded here and compare with features Scott wrote.

I’d like to clarify some facts about Firebird and Firebird Foundation. I think right now is a correct time to remind how all these things are organized, because some messages about "crisis, firebird's death, low finances" and so on being spreaded around.

I have a heavy-used website powered by LAMP stack (CentOS Linux,
Apache 2, MySQL and PHP). It started on a shared hosting so I had to
use MySQL. Year and a half later, I switched shared, virtual hosting
and not run it on a dedicated server. I decided to try Firebird to see
how it performs and also how it compares to MySQL in RAM usage, disk
usage, etc.

Firebird is trully *open* (in all aspects). Nobody owns Firebird, nobody can buy it, nobody can close its sources, nobody can charge for it! So, if you are using Firebird, you don’t need to have such worries.

Please join Philippe Makowski, President of Firebird Foundation, and Dmitry Yemanov, lead Firebird developer, at the Launch Webinar devoted to the 5th major release of Firebird. It will take place at October 4, 2010, at 13-00 GMT.

Now, this could be a very good opportunity for all of the other open source database servers particularly the most popular ones like Firebird and PostgreSQL. I’m particularly fond of Firebird (the InterBase offspring) and use it in many projects and did a lot of consulting to Delphi developers using it. Can this be the rise of Firebird?

I wrote the modification/tips needed for running RoR on Firebird

Migrations don’t work yet with RoR and Firebird but you can use Flamerobin for creating tables by hand

I decided to automate conversion of MySQL database to Firebird. I got
tired of manual find&replace process, and created a small parser that
changes from MySQL to Firebird syntax. Currently it only supports
database structure dump (no data, only structure) from PHPMyAdmin. Not
all datatypes are supported, but feel free to "fix" it. It's written