To a certain extent, what we put out there has to involve an individual threat assessment.
I always use my real name where ever I go and I have no qualms about telling people where I live. After all, I'm in the phone book and information about me is readily available in public records and on the back flaps of my books. My own observation has been that people who go around taking too many precautions cheat themselves out of many opportunities for enjoyment and profit, and that a lot of precautions aren't effective anyway. When I was single, for instance, I was advised to use initials for my phone book listing; but when you see a listing for "Smith, J," don't you assume that it's a single woman, just because you know single men have no motive to hide their identities? Whereas a lot of folks look at my peculiar spelling and can't decide what gender I am. (One magazine attributed both genders to me in the same bionote.)
The slim chance of someone encountering me on the internet and as a result deciding to read the books outweighs for me the slim possibility of being cyberstalked, and I want to talk freely about what interests me, which involves the occasional casual revelation of personal details. Also, I'm so far away from most of the population of the board that anyone who wanted to burgle me would probably spend more getting here than he would realize from fencing his take. (Specialty thieves take note: my husband and I deliberately buy the less "valuable" stuff for our collections - if we buy a first edition, we want the second printing, specifically because we get the same pleasure for less money.)
But that's my situation. Any truly public figure (say, Jenna Bush or Sarah Michelle Geller) who wanted to hang out in a public forum would do well to go in disguise.
I try not to reveal the personal details of other people; but reading this thread has made me realize how easy it is to accidentally reveal more than you had intended; and this concerns me far more than anything I might reveal about myself. If we lived in London, my story on the cats thread about kidnapping my neighbor's cat because I couldn't bear leaving her in the house all alone could have been truly dangerous. So I want any prospective criminals on the board to know that they're back now - I returned the cat this morning - and even when they're gone, my husband and I keep tabs on the property. They also live directly next door to the neighborhood Gossip Central, a retired couple who see and record everything that goes on. So stay away!