Mysql reliable with 1000 new entries / minute?
Prrffzzt. No, this isn't exactly high write load.

You should test yourself with your own data, of course. It depends on the kind of write query, the size of the table, the type of keys you're using. Explain  is your friend.

We have used MySQL as a backend for a major social networking website (high write load) without reliability problems. You can build impressive setups (as in: racks of servers just running the database) with MySQL.

You should consider MariaDB since many of the original MySQL developers moved there. You should also consider hiring a consultant if you are really worried about optimization and if your current solution doesn't scale.