The "Bank" in "BankSimple" was problematic for us. We're technically not a bank. We also don't want to be associated with the way people have approached banking, particularly in the US.
Sorry you're not crazy about the new name, but we're happy with it. It gives us a lot of room to grow.
There are actually laws prohibiting non-banks from using the word "bank" in their name. A lot of bank holding companies (which are not, technically, banks) got around this by replacing the "k" in "bank" with a "c" -- such as "BancAmerica Corp". I'm sure we all breathed a sigh of regulatory relief seeing that "c" there.
I'm a fan of the name Simple instead of BankSimple. I bank with ING and USAA at the moment, and I've never had any trouble with the fact that neither one has the name "Bank" in their brand.
I agree, calling it "BankSimple" feels limiting, and carries baggage from bad experiences I've had with banks in the past.
Now if only I could get an invitation to open an account!
Nitpicking: simpel.nl is actually a word joke, because they sell SIM-only cell phone subscriptions. So in effect their name does convey more meaning than "Simple" does, so it doesn't really belong in your list :)
Sorry you're not crazy about the new name, but we're happy with it. It gives us a lot of room to grow.