Not really, since the exchange rate changes, if you believe Euro will keep on getting stronger against the dollar you would want to keep your money in Euros and not USD. TM Trader
You didn't read very carefully. One can have a 'base currency' of USD but hold only EUR, Yen, or whatever in the account. Base currency is simply an accounting function.
The web site will be updated shortly as it is a "soft" launch. If you read the F&B discussion board on the IB side, the ability to wire out in different currencies is going smoothly and is receiving kudos from those who have tried it. You are probably better off opening an account in your home currency and doing and IDEAL transaction to the currency you prefer since IDEALs spreads are usually better than those you'll get by doing a similar transaction at your bank.