I used to but then again we're not really allowed to use our lap tops becaues of the WIFI at our school and then we just surf the web all the time. Also my lap top was just too big to bring to school so I just do the old fashion taking notes with a pen and paper thing.
When I did my graduate school I used my laptop for a big chunk of the classes. Anything that had a lot of info on the board or materials discussed by he professor I took notes using the laptop. I also kept a notebook nearby for figures and just referenced them in my notes.
It made it much easier to prepare for the exams.
The down side is that other students realized I had great notes, and started asking for copies.
I can't imagine why anyone would handwrite notes when they could type them. But, I type much faster than I write, and like ucfgrad93 said, I can read them later, and they are searchable.
Since I am attending DeVry Uni online, I print everything to PDF - text and lectures - and pull up that class's folder for fast searching during exams. It works quite well for me.
I also take my 17" MBP to church where I can access various Bible translations and text while taking notes. I am the only one who does it at the moment. But our pastor and worship leader both use iPads.
I brought up MR in church once and was very sorry I did. It is way too easy to accidentally pull up NSFW posts (even just some avatars are that way), and being in church, everyone is always looking over my shoulder.
Depending on how interesting the class is / how necessary it is to take notes then yes, sometimes I do. If the class gets boring I can just drift off into internet land.
I never take notes by hand, but I only ever rarely take notes in class.
I'll see next year (as teachers in Cégeps provide notes, and no one uses laptops anyways, so I don't bring mine), when I'll be in uni, but I guess I won't use it very much. Equations are written much more easily by hand