Well regarding X1 - It is the baap of all Nokia business phones. Enough said. The only major downpoint which I can see is a 3.2mp camera while comparing with the N96 which got 5mp camera. But still, people may choose it over N96 because of the Windows Mobile 6.1 Professional, Touchscreen, 384MB RAM, 528Mhz processor, full QWERTY keypad and don't forget, it also has the 3.5mm jack.
And those, who want to buy the N96, will be tempted to buy the N85 as N85 is virtually the N96 and will come at a much lower price.
While comparing C905 and N85, both have nearly the same specifications. The only major difference which I can see is Symbian and the 8.1mp camera. One got Symbian, the other has the camera. People who need an excellent 8.1mp true-camera phone and don't exactly require the Smartphone features, will surely go for C905 and those who want a Smartphone and can suffice with 5mp camera, will get the N85.
And yeah, believe me, an average customer who got $$$ doesn't actually bother comparing the phone which he wants to buy with other phones available in the category. Those who bother will definitely make the wise and the correct choice for themselves considering their respective requirements. We're fighting over no reason.
I don't see any point in arguing over this issue. Crap thread. And heck, why the fu(k are we comparing phones which fall in different price groups?? If you actualy mean NOKIA vs SE, then we probably got a thread in the Fight Club section. Continue there......:/
E90 is already history I believe, W902 doesn't actually fall in the group of N85 & C905, then we have Xperia & N96 which are 2 completely different phones intended towards 2 different types of public (atleast I believe this). No point in arguing over this issue I say.

And in the end, I believe we'll not actually be arguing over the features of the phone, we'll be comparing both the companies.
You guys should not forget, each and every phone sells. Probably, one person in every 10 people, thinks a lot before buying a phone. Others buy just like that.