Which phone are you using in particular? Some phones have IMAP on Hotmail, which enables push notifications for Hotmail, such as phones with HTC Sense. The stock vanilla Android email app uses POP3. I can't remember what Motorola or Samsung uses.
The way to check is to check the settings on the Hotmail account via your particular EMail app. If there is no mention of a POP3 for ingoing or SMPT on the outgoing server, then you have an IMAP account. That delivers push.
Or you can simply set up your Hotmail account via Microsoft Exchange.
There are also apps for the occasion:
Try among these:
K9
MailDroid
Moxier Mail
