I've actually had my N900 for ~6 weeks now and been logging impressions (naturally on the device itself) as I went. The time has come to publicize them; I'm hoping to:

• See if others agree with some of the shortcomings listed below so we can start brainstorms to hopefully get Nokia to address the main ones for the N900.
• Perhaps serve as pre-purchase advice for people who are wondering if the N900 is right for them?

My previous phone is a venerable N95 and I also own a 1st gen iPod touch (both 2007 devices). I've also test-driven an iPhone 3GS for 2 weeks last summer. So these are going to be my points of comparison - most of the shortcoming listed in this post are not issue for either or both of these platforms, ie: points where the N900 has some catching-up to do...

Let's start with general impressions:

• Hardware build quality is good - no visible or tangible wear & tear after 6 weeks.
• The OS is actually rather stable, especially considering how new it it. I think I've only experienced one spurious reboot and perhaps the odd browser crash - it actually feels more stable than the iPhone OS and certainly a great deal more stable than the N95 when it first came out.
• The OS and the phone are generally sufficiently responsive for my requirements - not outstandingly so but good enough. The only exception is navigating around IMAP email accounts - this is unbelievably sluggish (certainly when compared with my 2yrs old(!) iPod touch).
• Battery life is along the same lines, not great but adequate - daily charge is in order.
• Phone reception is actually a good notch better than the N95's and another notch better than the iPhone.
• In terms of features and usability, Maemo 5 is IMHO somewhat behind both the iPhone OS and even the N95's Symbian OS.

That last point, I personally feel, is where Nokia really need to step up the game with Maemo 5.

Shortcomings are being addressed: the recent 1.1 f/w update actually fixed a few of my gripes (listed below). Hopefully things are going to continue this way as there are rumours that Nokia may be concentrating on future releases instead of finishing the outstanding work on Meamo 5.

I've also tried to link existing brainstorms or bug reports. If you care, please visit them and vote; if you know of others that relate to similar topics, please follow-up on this thread and include relevant links...

My severity ratings: = low ; = medium ; = high

Email

• Display the number of unread mails on accounts overview screen (so I've received a few new emails but I have 5 accounts, now which one are they in??)
• Deleting emails from device doesn't delete them the from IMAP server; junk mail is annoying enough to not have to see it more than necessary...
• Cannot copy from email body w/o editing message first

Calendar (link to brainstorm)

• Unable to set specific time for calendar reminders (only "x minutes before")
• No sorting for notes kept with calendar (seems to default to oldest first which is pretty useless)
• Tasks cannot have descriptions or be linked to notes

Web Browser

• Provide shortcuts to go to top/bottom of pages; smth along the lines of CTRL+UP/DOWN as scrolling a long page can be painfully tedious (eg: iPhone lets you jump to top of page by tapping the title bar)
• Make it possible to enter history from the bookmarks page

Phone

• Cannot paste copied numbers into dialer as DTMF
• Redialling a saved contact's SIP call from the calls log dials using a cell connection

Media player

• No ability to rate tracks in the media player. In fact, there seems to be no support for ratings anywhere (display, use in smart playlists etc).
• No gapless playback...
• No robust way to sync music and related metadata from PC or NAS... yet
  

Others...

• The N95 would let me set the same PIN for SIM and device and have it prompted only once at device startup - not the N900... really tedious
• Lack of (customizable) profiles (eg: Outdoor, meeting)
• PDF reader doesn't support TOC (or other intra-document linking)
• "Maps" has no integration w/ other apps (eg: lookup/link contact's address on map)
• Some search/match functionality (eg: in selection lists for browser drop-downs) seems to be case-sensitive
• File manager doesn't respond to keystrokes to navigate contents - more tedious scrolling...

Now for the better news...

Issues addressed by latest firmware (PR1.1)

• Tasks couldn't have reminders (meaning they were next to useless)
• File manager allows browsing DLNA shares but when attempting to open files, eg: music, the media player would say it can only deal with local files.
• Auto time update doesn't seem to cope with timezone change when travelling

Issues reportedly addressed by forthcoming firmware releases

• Sending files via Bluetooth from File Manager