Just released new version of OmniPITR.
This version has one important new feature: when you're calling omnipitr-backup-slave, it will make backups only of required xlog files, and not, as previously, of all in walarchive directory.
This is important, especially in case you have multiple slaves, or you keep shared long-term walarchive. Previously – backups would get all files from walarchive (-s option to omnipitr-backup-slave), but now, it picks just the ones that are needed.
On somehow related note – I will be working now, finally, to get omnipitr-monitor functionality working.