As someone who regularly publishes in Interzone, and loves the other authors and stories they publish, it has been an irritation that Interzone stories weren't eligible for the Nebula Awards. I could understand this exclusion if the Nebula Awards focused solely on print publications from the United States. However, their rules state "Works first published in English on the Internet or in electronic formduring the calendar year shall be treated as though published in the United States." That has meant a story published in a minor British online magazine was eligible, while a story published in one of the top print SF magazines in the world wasn't.
However, the good news is that stories published in Interzone (and its sister publication Black Static, which I'm less familiar with) are now eligible. Since both are reprinted in an electronic edition through Fictionwise, their stories can now be nominated for the Nebulas. Aliette de Bodard checked and the SFWA Awards Rules Committee said yes, stories published in the Interzone and Black Static Fictionwise edition are eligible. This is great news!
It appears all 2009 issues of Interzone are eligible except for the current Nov./Dec. issue, which has yet to be uploaded to Fictionwise. This also means my novella "Sublimation Angels" (available at that link as a PDF download) is now eligible since the Sept./Oct. 2009 issue of Interzone is already available on Fictionwise.
I plan to soon add a few more selections to my 2009 Nebula nominations. And you can bet Interzone stories will figure in the mix!