Ian Lyons has posted details on downgrading from Lightroom 1.4 over at the Adobe Forums. Users affected by issues with DNG, timing and Jpeg previews should consider this option. If you’re not, 1.4 seems fine bar the issues.
On Windows, DNG previews are not created correctly. When you try to view at 1:1, an error message is displayed. One user has noted that this only happens on landscape images and not on portrait image. While I have confirmed the error, I’ve not confirmed the orientation report.
Other issues include the time being set to midnight on the export date in the EXIF with image Export. It’s not immediately obvious to a lot of users, because both Photoshop and Lightroom will show the correct time. This is because they are reading the internal XMP information rather than the EXIF. Use an EXIF reading tool to see the correct EXIF time.
Lightroom also appears to be writing times into RAW files when saving XMP. Normally the only thing that can change this is deliberate use of the Edit Capture time command. The RAW file shouldn’t be changed at any other time. Ian has confirmed this as a bug, rather than intended behaviour.
Certain Olympus users with a recent firmware seem to be having random JPEG preview issues. A smaller version of the file appears embedded in the main image. Thomas Knoll has asked people to post links to such pictures.
It’s unfortunate that such bugs have slipped into a bugfix release. I know the team will be straight onto fixing these. The only thing I might have found in my workflow is the time issue, but as I was viewing results in Lightroom, I would’ve missed it anyhow.