malaysian here. ive owned the n900 for over a year now. some of the things you said is true, like no 3g video call and voice command. but for the lagginess, try lurking moar in the forum. there are a lot of patches that addresses those problems.

for me, its the complete phone. ive tried to buy a new phone since owning the n900, but i could make up my mind because none of the phones in the market currently have the same features as the n900. we owe it to the OS, maemo.

but wait, theres more! you should be very happy because the nitdroid project is going very good and should you get bored of maemo (and i do not know why you will), you could always use android. and then, if u are more of a tech geek, check out MohammadAG's ubuntu for n900. and then theres also a debian build for the n900 on the web, the SHR and maybe next 2 - 3 weeks, MeeGo!