Just to make sure situation is more complicated, it is not the only NDA. I never signed this one, for example, but I signed PLA (product loan agreement) which also talks about admitting that provided developer device and its software may evolve before actual product sales release, therefore, developers are asked to keep from publicizing things that to be fixed in final product, like bugs or missing features. Quite similar language was in previous Maemo products' PLAs too. The line is a bit vague and you'll need to be a lawyer to really define it properly for some areas, though I think it is actually reasonable approach for in-development software and hardware.