n900 has lots of shortcomings - its just if you are a certain type of user you wont care about them

some are
- gaming - to get good native gaming you need a palm pre. for emulation you need to buy the actual game and fiddle around with emulator settings not to mention the legal grey area ( see nitendos reaction to the initial demo of n900 emulating snes). other then that n900 gaming is very poor.

- no ports of popular apps - few software houses support the n900 commercially

- community based apps - some see this as a strength but there are definitly downsides. with no commercial incentive and almost all apps written by volunteers - apps only get written when the coder has time or feels its cool. once the cool factor runs out or the coder has no time projects get abandoned and updates stop until someone else picks it up - which may be ages or never happen at all. some famous examples are opera (no flash integration) and psxemu with smoku leaving.

- nokia n ovi - no or poor support by nokia - see the initial release of the twitter app on ovi and also how difficult nokia makes devs who want to release stuff for ovi - look up the ***** threads

if u are a linux geek you wont care for the above but if you are a regular joe then you will care. thats y there is alot of disappointment because much of the downside is lack of fallow through by nokia which is their modus operandi by now.