Since its introduction in January, Mac users (new and old) have been waiting patiently for Time Capsules (TC) to start appearing in retail stores. For me - I got lucky and wandered into the Apple Store on Friday to find that they had actually materialized earlier in the day.
Getting the product installed into my home network was a little more difficult than I expected, but not terribly so. For me - the hang up was that I was not going to use the Airport Extreme Base Station (AEBS) to share out my Internet connection. My goal was simply to turn this device into another client on my Cat6 home network. After installing the AirPort utility provided with the packaging onto my MacBook Pro, configuring Time Capsule to recognize itself as a NAS only device was fairly straightforward. For at least the beginning, I disabled the wireless radio and plugged it in via one of its 4 available Cat6 connections. Opening config stuff was fairly standard: 1) give the device a name, decide on DHCP or manual IP config, etc. The only slightly annoying thing is that the Airport Utility does like to reset/reboot the Time Capsule after you make almost any type of change to the configuration. Mine must have rebooted 8 times before I had made the last of my changes.
As far as the integration with Time Machine, it was very intuitive and straight forward. The only curious thing is that it will not let me change my TM preferences unless my laptop was plugged in. Strangely, I could perform an instant backup with the laptop running on battery power. As many people have wondered, you can attach another USB-based hard-drive to the TC and use that drive(s) as the source of the TM backups if you like. Doing so would essentially make the entire size of TC available as traditional NAS Storage. Plugged in via my Ethernet connection, the initial TM backup of my 160GG (40 GB used) hard-drive took about 2.5 hours. I assume the speed would be significantly reduced if I was using the wireless. It looks as though Apple creates a sparse disk image bundle on the Time Capsule and then mounts that during a TM operation. This essentially leaves one file on the root of the hard drive after the initial backup is performed. You can mount this image at any time, and you will observe a folder structure similar to when Time Machine is operating against a locally attached USB hard drive.
Next the Wireless: After getting TM working to my satisfaction, I wanted to see if I set up another wireless network in my house. As with other AEBS units, this was very simple to do. I simply chose to put my TC into "Bridge Mode" and away I was. With 2 minutes I had a second wireless network up and running. For curiosity sake I setup the network to operate on the 5G Hz 802.11n configuration. I was curious to see how much faster the speed was than if I configured it to be backward compatible with 802.11a/b/g. Not surprisingly, performance on the "N" network was much better. I achieved average file transfers of almost twice the speed as I would have seen if I had been connected to my 802.11g network. Once I unplugged the Ethernet cable and went totally wireless, my Time Machine backups were very seamless and after a few hours of work, I stopped noticing the backups actually taking place.
Aesthetics: Like the AppleTV, the Time Capsule device does get fairly hot to the touch. From a size comparison, it is a little bit bigger (height-wise) than the AppleTV. It does not however have the smooth edges that the AppleTV sports. For some reason, its exterior design is more reminiscent of the last generation of AEBS.
Overall, Time Capsule is a great consumer device; but I have to believe that many power Mac users would cite SuperDuper's (http://www.shirt-pocket.com) ability to perform backups to image files stored on a network share as a comparable feature set in a backup solution. Interestingly, I am using both backup strategies: Time Machine & Time Capsule to protect the incremental versions of my everyday files and SuperDuper to generate a weekly backup image of my entire hard drive. My last comment would be this: a 500GB TC unit should be more than sufficient to take care of any single MacBook or MacBook Pro archiving strategy. If however you are looking to service multiple Macs or work with large amounts of video across the network, then the 1TB version will definitely be the way to go. Enjoy!