I got a Toshiba Thrive. I love it because it has a full size USB, HDMI, sdcard, amazing battery life, removable battery, etc. When I was shopping for a tablet last year I had my eyes set on the thrive, Asus Transformer, or the Acer Iconia 200. They all had great specs and full.size USB ports. The only thing that made my decision to go for the Thrive is that I told myself I would choose the first of those three that dropped below $300 and Thrive was the winner.
I would look for one that has full USB and decent specs. Full USB was important to me because it allows for allot more flexibility in using keyboards, flash drives, etc.
The Thrive is a very unique tablet. I owned one for awhile, and I really like what Toshiba tried to do with it. There's definitely a segment of the population that it's perfect for with the full-size ports and removable battery. But if you're looking to be as up-to-date and future proof as possible, Asus is the way to go. Personally, I think the TF300 is the best all-around tablet out there right now. Not only do you get top-notch specs, but you also get the best support in the industry from Asus, who is almost always the first to push out new updates. The TF300 has had Jelly Bean for a couple weeks now, and the Verizon Galaxy Nexus still hasn't received it. Asus is also extremely responsive in fixing any issues that might arrive. And the big plus is the keyboard dock that turns the tablet into a full-fledged Android laptop. If you're looking to try to replace a PC or a Mac, the Transformer line from Asus gets you closer than any others because of that dock (although, I will say that while you can be extremely productive with them, no tablet, even with a keyboard dock, is a true replacement for a PC/Mac at this point). In the dock, along with the keyboard, you get a full-size USB port (a great thing as TisMyDroid has pointed out for external drives and accessories, including game controllers), a full-size SD card slot, and extra battery life. You're looking at up to 16 hours of battery life between the tablet battery and the keyboard dock battery (and the keyboard dock charges the tablet battery). While there are higher-end Transformer options with the Prime and Infinity, the TF300 offers the best bang for your buck out of the Transformer lineup Asus has right now.
Too bad Best Buy doesn't offer the Nexus 7. That would be another great option that would leave you with some credit on your gift card left over.
I think bsweetness may have hit the nail right on the head... especially considering that Toshiba has been very slow with their updates. We only just got ICS. And the Asus is a spectacular tablet!