Linkdump: editing and related matters

A bunch of handy links/references related to editing:

• "That's the way to do it": The difference between "that" and "which", helpfully and clearly explained by David Marsh on the Guardian Style blog. I look this up every now and then, usually when a convoluted sentence trips me up.
  
• "The Most Comma Mistakes": Ben Yagoda at the New York Times gets down and dirty with commas and identifiers, and comma splices. My dad sent me this link last night and I knew most of this stuff but only intuitively --- not as sharply delineated as Yagoda's laid out here.
• And here's some good advice I've come across recently on how one can vet a freelance editor: a long, entertaining and insightful shpiel by user HapiSofi on the AbsoluteWrite forum, and Victoria Strauss's "Vetting an Independent Editor" on her blog Writer Beware.