He did it, in my opinion, the "geeky" way. On a public website, to his girlfriend, in front of millions of geeks.
What ever happened to on one knee when you are alone with a ring?
I thought about doing stuff like getting people to hold up signs, and announcing it on TV, or something of that matter, but I did it the old fashioned way. I know a couple women read my journal. Honestly, what way would you prefer?
I don't think women really dig the whole "geeky" way as much as they appreciate the personal time, especially when they can grab you and hug you, and generally be with you on one of their (hopefully) happiest moments.
Now, as a disclaimer, I think marriage is a wonderful thing, and am very happy for Rob & Katherine. Regardless of how he does it, it'll be a great time. Sure, he's happy now, but wait until she pregnant and moody