We have been using the new MEB for about a year in production. The improvements over the old InnoDB Backup are phenomenal and allow us to backup with somewhat regularity.
We are on our way with the parallel features of reading and processing. From our standpoint of an enterprise, it would be really nice if we have the ability to output to multiple devices similar to RMAN's channels.
For example, we backup to disk. If I want to backup a 1TB database, I have to have 2TB of space available (1TB for yesterday's backup, 1TB for today's backup in case we have a failure during the backup). In addition, that 2TB filesystem is going to get pounded, especially if I am using multiple readers. If we could tell MEB to use TWO 1TB filesystems, that would give us better performance as well as manageability.
Just something to think about.