I would like to see more persistent phone status icons, for example currently it is too easy to dismiss a voicemail or sms notification and forget about it. Most phones put indicators into the status area when such an event occurs. I find myself forgetting about voicemails as I dismiss the initial message and then when I do check I've missed something from several days ago.

Also you should be able to set customizable reminders up on these events so that you will not easily forget.

I also agree with MartinNZ, but I would take this a step further - everything in the phones firmware should be linked together, for example:
1) contacts should be able to be added to the calendar
2) addresses in the calendar should be able to be linked to ovi maps and vice versa