While many of the above posts discuss the transition into graduate school, many students are already looking beyond the hallowed halls of their own degree programs. In fact, a great deal of discussion about graduate school concerns the degree to which graduate students can and should be preparing for academic careers beyond the PhD program. While faculty are intimately familiar with the Teaching / Research / Service division of labor, graduate programs often offer uneven preparation on this balancing act. The following posts (some of which themselves link to excellent posts) offer plenty of food for though on the process of professionalization.
Dr. Virago's post at Quod She on professionalization, like the posts with which she is in dialogue, is notable not only for the insight of the post, but of the excellent discussion that follows in the comments.
Similarly, Lisa Chase offers her considered input.
Both Flavia of Ferule and Fescue, and Dr. Crazy at Reassigned Time offer up excellent advice on networking .
Dr. Crazy also offers up an important take not just on teaching (for which advice is abundantly available) but on learning to teach as a graduate student and as a professional.
And finally, Barnet Bound asks us to consider that bastard stepchild of the whole balancing act, service, as it fits into the larger picture of graduate student education.