For this to work, you need to be connected to the internet 24/7. You also need to be connectable 24/7 letting the email service send the message to you. What happens if you are on a NAT:ed network behind a firewall or router (which is very common)?
I let the email client on my phone check for new emails with regular intervals making it the active part which works everywhere. I have trouble imagining any situation where I need to know about a new email the same minute which would justify being on-line 24/7. If I'm waiting for something important, I click "Check for new email" by hand as often as I want or need.
A push method makes much more sense when used with a stationary computer that's connected to the internet at all times. The value for mobile users feels almost nonexistant.
Second of all, if the value for mobile users was non existant, why would every major device - including the N900 - have this option? Why would most mobile service provides offer their own push services for business users?
Not only that, but some devices boast their push abilities as a selling point - Blackberry for example.
For me its simple, sometimes I reply emails the very instant they arrive with short answers. I exchange several mails during one mail conversation in a matter of minutes. As the recipients of my emails often have push on their devices, responses arrive promptly as well. Some people check mail several times a day, while others treat it almost as IMs.
Now, I understand you don't need it, but this doesn't help me in any way. I asked a question with this thread, if you don't know the answer, please don't reply with "you don't need it". Just ignore it.
I ask to learn. And I'm not saying anything about your needs. You obviously use this feature very much.
When it comes to what is said in advertisements, I do try to separate "actual value" from "this looks good in an ad".
For someone who uses email as IM, this definitely has its uses (given 24/7 connectability). I just let my email client check more often or use an actual IM client. To each his own.
I seem to get messages to my hotmail.com address immediately lately. Not sure exactly why - message read status seems to be syncing now as well - using Nokia Messaging.
