Microsoft has just released a newly updated version of SharePoint Service Pack 1.
As posted previously, Microsoft released SP1 and then recalled the update because it was going to have future compatibility problems.
For those customers who previously installed SP1 and are wondering how to fix the problems in the previous version, the prescribed advice from Microsoft is as follows:
Customers with Service Pack 1 Deployed
For customers who have previously deployed Service Pack 1, download the updated Service Pack 1 and install over the existing Service Pack 1 running PSConfig or PSConfigUI immediately following.
As with most service packs, you might want to wait a little while before installing this update and make sure you test it thoroughly before deploying to production.