Update: Opera has crashed on me once so far. no biggie. other than that i'm enjoying the browser. A feature I really like, is the Opera Mail. It goes so much further than IE or Firefox in that aspect. Internet Explorer only has the Windows Live toolbar that shows you what mail you have via a preview. If you want to do anything else, you are redirected to ur mailbox online. Opera totally 1up's IE on this front. It has a built in full fledged mail client that you can configure to synchronize with you regular email service. e.g. Hotmail. You can access your mail directly from within the browser. No need to navigate away to another tab to open your email. Everything you are accustomed doing with your regular mail is featured in the built-in client. I'm not sure if this feature was present all along. Like I said I haven't use Opera in years.
Another feature I like is the mouse gesture feature. I sort of stumbled onto this. Mouse gesture is using your mouse to navigate around a web page in a unique and simple way. Nomally if you want to go to another page, you left-click on a link. With mouse gesture, you press and hold the "right-click" button and simply drag (quickly) the mouse to the right if you want the page to go forward. Or to the a snap of the wrist to the left takes you back to a previous page. This can come in handy if you're reading a book or document online that has multiple pages to skim through. There are other gestures to accomplish other tasks but i'm not familiar with them as yet.
Stay tunes for more.