It takes a little while to build up a complete list of the most blatant spammers but,eventually you will have far less junk to deal with. Outlook allows you to block all incoming email from an email address so every time I receive a piece ofJunk/Spam, I block all future incoming traffic from the sender. The one area where I find outlook to be superior to Apple Mail is in the handling of Junk Mail / Spam. In a similar fashion dates / times will provide ability to automatically set an iCal event and a very useful tool is that tracking numbers for UPS/FedEx/USPS (and possibly other carriers that I do not use) provide quick links to open the appropriate web page and track that particular shipment. Hovering your mouse over the contact information will display a pull-down menu letting you add the information to your contacts. Within an email containing someone’s contact information mail creates a virtual hyperlink to your Address Book. It also has much tighter integration with the OS and ancillary Apple applications such as iCal, Address Book (Contacts), Safari, etc. The most obvious advantage to AppleMail is that it is free. There are plusses and minuses to each product (Outlook & Apple Mail). I have also lately begun to play with the new Lion version of Mail on my home computer.
I previously utilized Entourage from Microsoft Office Mac (2008) and now Outlook for Mac(Office 2011). I can't speak to Outlook 2007 since I have never been on the Dark Side (Windows) for my main services such as email.