As expected there was an issue with 1.4.8. This is unusual for us but given what the changes in 1.4.8 corrected, it was important that they were fixed. Unfortunately the regression posed significant issues so we did an emergency release here.
In 1.4.8 we advised people only to upgrade if they were affected by the bugs listed. We now have confidence that the changes are stable on 1.4.9. It is a better time to upgrade but if you want to be cautious, feel free to wait for 1.4.10.