Sony announced today that it will be abandoning its proprietary e-book format and DRM in favor of Adobe’s Digital Editions platform and the standard ePub file format.   Sony’s Reader e-book devices have supported the Adobe platform for a while, but by the end of this year, they will support it exclusively.

This is a win for Adobe, as the Sony Reader family is widely acknowledged to be the second most popular e-book device, after the Amazon Kindle.  But it equally indicates the uphill climb that Adobe has in front of it in order to remain a contender in the e-book market.

It’s classic technology market behavior: to use the terminology of tech marketing guru Geoffrey Moore, the chimps and monkeys in a market typically band together to try to compete with the gorilla.  Technology markets tend to have one, two, or at the outside, three gorillas.  Right now, Amazon is the first gorilla of e-books.  Barnes and Noble, together with its eReader acquisition, may become the second.

But is there room for a third?  And if so, who will it be?  Some are pointing to Apple’s pending entry into the e-book market via its heavily rumored tablet device combined with iTunes as the retail platform.  Others are waiting for Borders, the only serious competitor to Barnes & Noble in the brick-and-mortar book retail market, to announce its technology dance partner and launch its own e-book strategy (beyond selling devices within retail stores).

Adobe risks a future in which it becomes to e-books what Microsoft became to digital music: a software supplier to a bunch of chimps — i.e., also-ran consumer electronics makers.  By offering technology components into an early market where consumers wanted end-to-end solutions, Microsoft got the timing wrong.

Adobe’s platform is not currently used by any retailers of significant size.  That’s a big problem.  Yet there are a couple of ways in which Adobe could prevail in e-books yet.  First is the possibility that Apple licenses Digital Editions for use in its forthcoming tablet device.  Given Apple’s existing DRM technology and history of in-house development, this seems unlikely.

The more promising strategy is for Adobe to work with the next generation of e-book reading devices — thinner, lighter, faster, cheaper, with color displays, more memory, and so on — and promote interoperability among all of them.  This could drive a growing number of consumers away from the less-interoperable Amazon ecosystem.  Then if the Adobe-based devices prove popular enough, Amazon may capitulate and support them after all, especially if Amazon finds that more of its profits are going to come from sales of e-books than from e-book readers.

But to reach that point, Adobe and its partners still need a sufficient retail presence.  Wireless delivery of e-books directly into the device, which the Kindles support now, will help avoid dependence on established retailers.  Adobe will also continue to benefit through its ability to support public library e-book lending through the service provider Overdrive, which just announced a joint marketing agreement with Sony.

With several e-book reader vendors poised to announce new devices with Adobe support, the probability of Adobe’s success will become more apparent in the next several months.