Most serious users of MySQL have moved their tables to InnoDB years ago. For those who haven't, let's discuss why InnoDB is a more scalable solution than MyISAM.
MyISAM was designed to be very fast for read queries. It does not handle higher loads of writes very well. It also suffers a more serious flaw: it isn't crash-safe. In other words, you better have frequent backups.
MyISAM tables