Does anyone know which (if any) of the carriers offers the choice of a microsim card. I'm toying with the idea of getting an iPad 3G when I'm next in the US, but the damn thing only takes microsim.

from a quick search it doesn't look like, even though they'll start once the IPad go for sale here - but can't you just trim down a normal sim card? I think the circuitry is the same

The chip is absolutely identical, so you can safely cut the plastic around it. Here are the sizes and the source.

yup. just cut away the extra plastic. you can also buy shims to fit a usim back in normal sim size phone.

my first phone was a motorola which used the full credit card sized sim!

I really don't get what the thinking behind using the microsim was.

reduce size of SIM to leave more space for a bigger battery

Thanks guys. Reading the wiki article on sim cards, it seems like the microsim is an evolution over the regular sim in terms of having more memory, enhanced security (new encryption of data, hierarchical pin management, universal pin, application pin, local pin etc..). It also promises storage of email addresses, groups and alternative names in the phonebook and programming for mobile purse (or e-wallet) which could mean paying for items from your device

So I'm wondering whether some of the iPad's functionality would be lost by using a trimmed down regular sim

I'm pretty sure the reasons castro listed seem more likely.

i assume the real reason was to make it easier to lock-in to certain telco partners

That's what I thought!

But if you just to do some cutting then that is redundant?

that's an easy one: that way Apple and the phone providers can force their customers to get new / additional subscriptions.

true but cutting a SIM-card is harder than you might think - I tried that a couple of times for Turbo-SIM, back in the good old iPhone 1.0 days. I screwed up about half of them.

How will they manage that?

i'm sure that would put off at least 80% of people from doing it. probably 99% of Swiss people

You can't use your existing SIM-cards in the iPad and they'll only give you a micro-SIM if you get an iPad-specific subscription.

Are you tempted Peter?

read this: The Apple iPad

:-)