Let the hive mind of Engadget get that for you.
"I finally got a new laptop with a lone USB 3.0 port. I'm now looking at getting a USB 3.0 hub with a power adapter so I can use both of my USB 3.0 hard drives at faster speeds. I've read lots of horror stories where some hubs either don't come with power adapters -- and as a consequence the portable drives don't work with them properly -- or they are designed poorly which results in USB 2.0 speeds. Or, the hard drives keep getting disconnected. Do your readers have any suggestions or experience using USB 3.0 hubs? Thanks!"
Don't stress about the WP7 deal.
If you are on T-Mobile's Even More plan you now get 12 month upgrades which includes getting the full upgrade price on smart phones. So, you can get the HD2 now and in 12 months, get yourself a new WP7 phone.
We are still at least 6 months from seeing WP7 and there's no guarantee that we'll see a WP7 device on T-Mobile right away either. Let's say it's the end of 2010 or even 2011 before T-Mobile sees a WP7 phone... at worst, you're 3 months from your next 12 month upgrade.
If it's the $$$ you're stressing about, the street price on an HD2 in 12 months will be more than enough to offset the price of upgrading to a new WP7 phone.