People keep saying this, but are not really looking at long term. Lets say you (like me) buys a 64 GB iPad 3 on the March 16th. What can apple put in the iPad 5 to get you to buy it? Sure more flash, but if the android tablets can take a 2 TB SDXC card, and Apple is topping out at a 128 GB model, thats going to be on every single advertisement. Everyone talks about Apple pushing the Cloud, sure they are pushing the cloud, but they are also pushing the Post-PC world, and in the post PC world, people want to have the data they have on their PC on the Post PC device. Card slots are just one possible solution (and apple may go with another, I talked about portable clouds for instance) but its an easy one to use and its not like Apple isnt putting a SDXC cardslot in each and every Macbookpro.
-Tig