Yes, the issue with the portrait keyboard is coming up with something that fits 10+ characters on the same row, while still being usable.

You can in theory do a design where you zoom the key after each press, then let go when you're on top of the right key. But solutions like that (for instance in the iPhone) use an additional predictive engine to "smooth out" / guess what character the user was actually pressing. Without the predictive component the experience simply wouldn't very good.

Of course you can say that you just need to type so that you carefully select every letter there, but then the typing experience wouldn't be very satisfactory. The bar of just turning the device to landscape and typing with the nice HW keyboard gets very low - and if so, the bother of making that keyboard in the first place might get lost.

(Qgil has the additional point about one hand use: if portrait keyboard requires two hands, you might just as well use these two hands to turn into landscape.)

So you prefer to stick in portrait and type a text on a T9 rather than turn the device and type the thing on the comfortable keyboard? Seriously?

@qgil: I think if you read the use cases in this thread carefully, most of them talks about certain constraint that limits yourself to a one handed use. Either lack of time or lack of additional biologic appendage to deal with extraneous objects around us. Yes, you can blame or argue the person that they shouldn't be doing that in the first place for whatever reason (Ethic, efficiency, etc) but then again people have been doing that already with 99% other phones (and smartphones) that this is what they expect out of N900.

I personally think the N900 has to be heavily marketed as a miniature computer (or anything than a smartphone competitor) to take it away from any comparisons against other (Smart)phones and so that people have different expectation of what kind of interaction experience they will have with this (no one handedness, for one).

The Danger Sidekick, sold by TMobile US (see a common thread?)

People want to be able to choose!! Not to be limited!!

Simple as that!

Such an expensive device, lacking way behind with regards to software, should support both landscape and portrait mode, to justify the price..

And yes, in most cases I would choose portrait mode, and not have to use both my hands just to answar an sms..

And this is what Nokia is doing. Maemo is for mobile computers. If you want a Nokia smartphone you have a wide choice of models with Symbian inside. Check all our communications and you won't find the N900 defined as a smartphone, or Maemo defined as a smartphone OS.

Just like in the iPhone, where portrait and landscape mode is fully supp...

Oops.

How about something like this:

Guys. This is such a non-issue. If this 'OMG I'll have to flip to landscape to type an SMS' is the N900's biggest ergonomy problem, I'm very very happy.

http://www.apple.com/iphone/iphone-3gs/keyboard.html

Well, the iPhone supports 100% apps in portrait mode.

As of OS 3.0 all of the build in apps can function in both portrait and landscape (yes, including the calculator which becomes a full featured scientific calculator in landscape) and a good majority of popular productivity apps (Evernotes, Pocket Informant, Toodledo Notebook, etc) have support of both landscape and portrait mode.