As was to be expected there was an issue with 1.4.8: given the issues 1.4.8 corrected - and the changes required to do so - it was important that they were fixed and by consequence to accept the -likely- chance of regressions. Unfortunately this regression poses significant issues which explains the emergency release.
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. All users should feel free to upgrade to 1.4.9 (the upgrade restriction has been lifted); however, if users don't feel confident, they should feel free to wait for 1.4.10.
The only issue fixed in this release is the fact that customers, vendors, and employees can not be viewed in version 1.4.8.