Geeks aren't the only people using SD cards in cameras, USB drives with computers, and Blu-ray discs in their home theater setup. External data storage isn't a tough concept for people. (With that said, it'd be better if we didn't have to worry about it.)

This isn't thinking like a geek, I'm sorry. comparing the internal storage on an Android/Firefox OS phone to an iPhone is comparing apples with oranges[1]; consumers know about SD cards and have done for years.

[1] no pun intended, although given my Keon's case colour, it is quite a good one :)

melling, being able to accept a microSD card is a big deal even to people who are non-techie. My wife takes many, many pics and having a 32gig microSD card is very good if you like take pics, record vids, have music and have a bunch of kids Tv shows to calm a child. I don't even take many pics, and my Samsung Galaxy player with 5 gigs internal and 32 gigs sdcard is almost filled.

While useful, of course, I don't think it's as big of a deal as you suggest it is. If it were, the iPhone wouldn't be as popular as it is, for instance.

Just because the iPhone is popular without microSD expansion doesn't mean the feature isn't a big deal. It's still important enough to be a deal breaker for some people. It's definitely not a feature only geeks care about as the OP seems to think.