Today, Adobe posted a release candidate of the Camera Raw 4.5 plug-in via the Adobe Labs website. By release candidate, Adobe means that the software is well tested, but they would like to see additional community testing before it is automatically distributed out to all the installations of Photoshop out there.

The release notes for this release are are pretty sparse, but indicate that this version of Camera Raw includes support for the Olympus E 420 and E 520 cameras. That's it. That might make it seem that this is a pretty light release, but with the upcoming release of Lightroom 2.0, it's pretty safe to bet that the only visible improvements to Adobe Camera Raw from the standpoint of Photoshop users is support for the two Olympus cameras. After all, Lightroom uses ACR as its processing engine and the upcoming Lightroom 2.0 release sports all sorts of new features, including localized corrections and post-crop vignettes. Historically, as Lightroom has pioneered new features for RAW processing, ACR plug-in releases have supported so that Photoshop (and Bridge) can interoperate with Lightroom.

Based on history and general cloud watching, I'm happy to see this release of ACR 4.5 as it most likely means that we're one more step closer to seeing Lightroom 2.0 come out the door and to be able to open RAW files with localized corrections in Photoshop. Support for two Olympus cameras, sure. That's fine. But laying groundwork for a new release of Lightroom, well, that's really cool.