Nokia has been hard at work building Maemo 5, the next major version of its Linux-based mobile platform. This new version, which is codenamed Fremantle, brings a user interface overhaul and some compelling new capabilities. Although Maemo 5 is still at the beta stage of development and Nokia has not yet announced when it will ship on actual hardware, details are already emerging about the version that will come next, which is codenamed Harmattan.

Nokia first published the preliminary roadmap for Harmattan last year at the Maemo wiki but disclosed very few additional details. Earlier this week, alleged screenshots of Harmattan and a considerable amount of new information about the platform were leaked and published by MobileCrunch. According to their informant, Harmattan could arrive at the end of 2010 and is potentially going to be available on a smartphone device. The informant also claims that Nokia's long-term plan is to eventually ditch its Symbian-based S60 platform and adopt Maemo across its handset line.

These are all highly speculative claims and none of it has been confirmed yet by Nokia, but there are some very clear signs that suggest some of it could be true. A very significant point that appears to have been overlooked by MobileCrunch and other gadget sites that are covering this news is that Nokia recently launched a joint project with Intel to build a full Linux telephony stack—one that could be used to bring voice calling to Maemo. This project, which is called oFono, was announced earlier this month. Nokia clearly aims to build the software that will be necessary to deliver a Maemo smartphone.

A big question here is what this will mean for Symbian. Nokia is investing considerable resources in an effort to open the Symbian platform and make it more competitive relative to Linux-based phone operating systems. Given Nokia's strong affinity for Symbian and the lengths to which the company has gone to make itself the arbiter of Symbian's destiny, it seems hard to imagine Nokia simply phasing it out and walking away.

One possibility is that Nokia intends to continue using both platforms for a long time during a gradual and highly protracted transition process. Another possibility is that Maemo will never completely displace S60 and Nokia will simply commit to using each one in certain segments. Regardless of which approach Nokia takes, it seems likely that Qt is going to be the common layer that facilitates the transition. Nokia's recent port of Qt to S60 makes it easier to build applications that can target both S60 and Maemo. Harmattan is said to make extensive use of Qt, unlike Maemo 5 and all previous versions which have been built on GTK+.

I'm inclined to think that Maemo would make a pretty good smartphone platform. Its strong Linux roots and close alignment with upstream desktop Linux technologies would make it a more appealing option than Android for many third-party developers and hardware makers who don't want to get locked into Android's insular ecosystem. The ability to take the vast number of existing desktop GTK+ and Qt applications and port them trivially to a smartphone is also an appealing factor. The advantage that Maemo offers over Symbian is easier application development and a more modern platform stack.

Ever since the first Nokia Internet Tablet device hit the market, a number of our readers have challenged the relevance of the product and argued that there is no compelling reason to carry an extra handheld device alongside a smartphone. Indeed, my own use of the Nokia Internet Tablet has largely declined as a result of significant advancements in smartphone browser quality—a trend that is clearly accelerating. Several other staff members who owned N800s have expressed similar sentiments. A Maemo smartphone could have the potential to be a real winner and would make the platform highly relevant again.

The legitimacy of the information that was leaked to MobileCrunch is still in question. The timing of the leak—the night before the official release of the Moblin 2 beta—makes it look a bit suspicious. I'm enthusiastic about the prospect of a Maemo smartphone, but I think it's still too early to draw a whole lot of solid conclusions from the information that was exposed by the leak.