Which opensource database to choose?

Please post your thoughts about firebird on this interesting Linkedin thread on the Firebird community’s page

Which opensource database to choose?
Hi,
I have realized that the “opensource” alternatives to commercial databases / operating system are growing really fast now.
My question to you: experts here are:

What benefits will it be to select a firebird SQL database?

What market will suit best for firebird SQL Databases?

Regards Tomas