From personal experience with that very drive I can tell you that it comes pre-formatted with the NTFS file system format (Windows - specific) AND it comes with some add-on Western Digital software that you absolutely DO NOT NEED OR WANT TO INSTALL.
When you get your drive, simply plug it in so that it mounts to your computer, run the Disk Utility application that is in your /Applications/Utilities directory, highlight the disk partition (not the drive mechanism listed just above it) and then choose "Erase" and pull down the list of formats to HFS + Journaled, then click OK.....you can rename the disk to a name of your liking. The result will be a Macintosh - specific formatted hard drive that will perform exactly the way you desire for your Time Machine needs.
Rats! You beat me to it (by about an hour). I was out shopping (see below) when you posted this item. Here's my take:
Man, that was slick! But first a little history ...
Given the crapola (ie, flooding) in Thailand with respect to external hard drive factories (which may or may not ever come back on line) and otherwise indefinite plans of external hard drive purveyors (eg, Western Digital), 1TB drives under $100 (much less in the $70 arena) are going to be few and far between. So I went to a local big box store and grabbed a WD My Passport 1TB drive on sale.
It took me longer to get it out of the box than it did to connect it and get my first backup started (ongoing as I write this). Upon plugging it in, my iMac asked if I wanted to make it my backup disk, to which I answered in the affirmative, whereupon it immediately opened Time Machine, reformatted the drive* and gave me 120 seconds during which I could choose the option of aborting the first backup, and then went into the backup. It took about 90 sec/GB for the initial backup.
[* It just did it. No options, no list of formats. It knew where it was going and went there. Another new feature of Lion (which Pogue also alluded to).]
Ain't too shabby. And now I've got an external source to recover the entire system plus my files. Sweet.
