You're right, ING is probably out of the competition. Hopefully, Emigrant will stay in the race.
I just started an account with HSBC. You can apply online. First you have to verify the two small deposits (just like ED and ING), But then you have to wait for them to send you the temporary id and password in two separate letters (postal mail). Then you can log in. After all this, you then have to set up for ACH transfer links. You either need the PIN from your ATM card (that's sent in a third letter) or you have to call and have the rep set it up.
About the signup bonus, I tried this one
http://hsbcdirect.com/1/start.htm
with the promo code "start"
When I called about previous bonuses, I've been told these are intended for targeted customers. However, I've read about many people being able to get these bonuses. If I don't get the bonus, I probably can't complain.
Your strategy about sending your money to the bank with the best rate is fine. One thing good about HSBC is that they have an ACH transfer system that's easy to set up and can link to non-checking accounts.