1-up! While Apple says the new MacBook has a memory limit of 4GB, memory retailer Ramjet says that the limit is actually 6GB. You get to that magic number, six, by using a single 4GB module and a singe 2GB module. On Ramjet that costs a whopping $680 $580—$500 for the 4GB module and $80 for the 2GB module.

Now, MacRumors says that the new MacBook Pro has a memory limit of 8GB. That’s all well and good, but OS X seems to run into issues when using anything more than 6GB of RAM.

Meanwhile, I’m using this MacBook with 3GB of RAM. I’ve got WebKit (with 15 tabs open), iTunes, Adium, Photoshop CS3 (still haven’t, ahem, upgraded), NetNewsWire and TextEdit open (with less than 3GB left on the hard drive)—everything’s running fine here.