Sorry, but the N900 is NOT "smartphoner" friendly and I have been warning about this for a while in regards to their assumptions.
1. Where is MMS?
2. Where is portrait?
3. Where are the apps?
4. Wifi and GPRS issues
5. Battery problems (I think this is mainly due to Flash)
6. Codec issues
7. Media player issues like playlists 8. GPS problems
9. Emulator issues (not as good as WM or Android options- yet)
10. Stuttering video at start-up
11. Youtube stuttering and HQ not as good as other devices.
12. People messing their N900 up due to installing out of "safe" repositories
13. Apparently weak USB connector
14. Weak 2G reception for low areas
15. Blurry flash photos 16. Problematic auto focus
17. MP3 player can be a stuttery mess when browser is open and using it.
18. FM radio signal is weak
19. Where is the file indexing? The OS seems to refresh everytime you open a directory.
These are just the things I thought of in a few minutes, but all have some truth to them to at least a trace level. If just perception, the point is the issues are perceived as problems.