I don't see this big urgency about winning with Maemo 5. Nokia has consistently said Maemo is a multi-step program and the N900/Maemo 5 represents the penultimate step. No need to panic.

The mobile device situation is very different from the desktop war to which people on this thread keep referring. Microsoft was able to marginalize everyone else because businesses needed to be on the same playing field with one another. You couldn't have a Mac and expect a person with a PC to read the file you sent him. Desktop-based apps were only going to run on the platform for which they were made. And Microsoft did some really nasty anti-competitive things that they got away with.

Mobile isn't the same. For one thing, insofar as so much is web-based, there is inherently a degree of interoperability among platforms that didn't exist in the desktop wars. Until Google can defeat Microsoft (not happening tomorrow), things like Microsoft Exchange and Microsoft Office still matter, and Nokia's partnership with Microsoft places Nokia in a good position.

Something like WebOS can fail because Palm just won't have the money to keep developing the OS since it's market share has already fallen so much and it isn't selling enough units of the Pre. Nokia clearly doesn't have that problem, and it isn't going to get shut out by formats and interoperability issues like happened to Microsoft's competitors.

Maemo has fewer apps than iPhone or Android now have, but it clearly didn't take all that long to create those apps. If thousands of apps could be quickly created for the iPhone, they can be created for other OSes so long as the tools are provided and the market size is there. Also, I don't see the apps themselves as tying someone to a platform like MSOffice-based data did. People do get tied to iTunes if they aren't tech-savvy, but I wouldn't be surprised to see anti-trust open that up. And if not anti-trust, then simple migration programs provided by smart competitors. Most of the "data" that phone-users have is not proprietary and can be used elsewhere. So at least for a while, users will be able to migrate back and forth among OSes in a way that didn't happen much with desktops.

Insofar as there is stuff like Kindle data (that is, books that can only be read with a Kindle reader), migration is tough; but that's one of the things that has slowed growth of the Kindle market. I think most formats will work on different OSes, even if they have DRM protection, like what Sony is doing with its eReader. Consumer insistence on relatively open or interoperable formats will help keep multiple OSes viable.

So, in sum, various OSes will compete for a while so long as their creators have the wherewithal, and Maemo, which is a pretty cool OS and has a big manufacturer behind it and interesting synergies with Symbian (QT), has a good shot at a good future.