since you're posting here, you have a grocer's apostrophe on the home page... it's "URLs", not "URL's".
second, can we auto-migrate somehow from a posterous backup - my wife runs a blog on posterous and is really worried that she needs to migrate. if i could tell her that she just now needs to pay $5/month and not rely on me to hack something together w/octopress and github she will be so excited.
This is one of the first features we will be launching in the next two weeks: Posterous import. This is a high priority as I have years of data on there as well. We're putting the finishing touches on it as we speak.
Depends on your style guide. Sometimes the apostrophe is preferred for abbreviations because it separates the s. ie, it's not something I'd correct somebody for unless we had specifically and previously agreed to a particular style guide.
I think you are being a bit hard on tedunangst since his statement "Sometimes the apostrophe is preferred..." applies in situations different from your examples.
For example: "The Times (and some other publications, including the Chicago Manual of Style) do call for using an apostrophe in the plural of abbreviations that include periods."
By both those references, it's "URLs", not "URL's".
rubyrescue: since you're posting here, you have a grocer's apostrophe on the home page... it's "URLs", not "URL's".
tedunangst: Depends on your style guide. Sometimes the apostrophe is preferred for abbreviations ... not something I'd correct somebody for unless we had specifically and previously agreed to a particular style guide
tedunangst claimed that was a style choice. It's not. By all these guides, "URL's" is wrong, and is something that would be corrected by editors using your examples of NYT or Chicago Manual of Style.
Also, for the periods, omitting the periods is often the cleanest answer. Instead of "C.P.A.'s" which is both ambiguous and ugly, consider "I went to my CPA's office. Naturally, it was full of CPAs."
You're safest following this line from your Wikipedia link: The MLA is explicit "do not use an apostrophe to form the plural of an abbreviation". The APA is specific in "without an apostrophe".
OT: "grocer's apostrophe" -- never heard someone use that phrase, and I really like it. I see that all the time, and it makes my skin itch. I will be borrowing it frequently.
second, can we auto-migrate somehow from a posterous backup - my wife runs a blog on posterous and is really worried that she needs to migrate. if i could tell her that she just now needs to pay $5/month and not rely on me to hack something together w/octopress and github she will be so excited.