There's also a series called Bakuman, which appears to be about two characters creating a manga series; it's by Death Note creators Tsugumi Ohba and Takeshi Obata, which makes it worth checking out, even if the only chapter currently available is the twelfth one.
And while I can't seem to get either one to download, I'm quite intrigued by a pair of chapters in which creators illustrate each other's series: Takeshi Obata takes on Yoshio Sawai's BoBoBo-Bo Bo-BoBo (read my review of that series here), and Sawai reciprocates, offering his version of Death Note (and why not read my take on volumes of that series here?). Sounds awesome; I think I'll scour the internets to try to track those down.
So, yeah, online manga: wave of the future. Like I didn't have too little free time already.