Not sure oif anyone else has already posted this - but there has been an update and 4.1 is now available for download.
Photoshop Lightroom beta 4.1 was posted on 10/19/2006 in order to resolve some issues with the original beta 4 build. The following bugs were fixed:
There was an issue where a user could not edit a metadata field after editing it for another picture which has been fixed.
The preview cache was using wrong relative path.
There were a couple fixes in the database update feature, fixing a few situations where the database would not update properly. Also, upgraded libraries would not always allow images to be moved between shoots.
There was an problem selecting an existing folder for web galleries. The web gallery would move all images previously in the folder to the trash silently. This has been fixed. All contents of directory where a web gallery is saved are sent to the trash with no warning. Also in web, large exported galleries will now have all the images expected.
The app had a couple unexpected failures canceling dialogs. Selecting cancel on the Enter Password dialog now reliably works, as does selecting cancel in Page Setup.
The shoot selection should no longer change unexpectedly.
The "Additional External Editor" preference and the "Edit in Photoshop" preference are now separate.
If you had mixed managed photos and by reference files, the paths of by reference files would be changed when changing the location of the managed folder.
Images exported with Constrain Pixels would produce the wrong result for portrait-oriented images .
There are some changes in the relationship between Luminance and Saturation.