Just like last year, HTC will be offering: the Double Dip case, which will allow you to mix and match case pieces with up to four color combinations; the Flip case, which will offer various color options with the flip cover to protect the screen; the Battery Bar, to allow you to charge the device on the go (although early indications make that seem unnecessary); the Car Kit, to help you mount your device to your car's dash; the Fetch, which will help you find your phone nearby, or take a remote picture; and the Mini+, which is essentially a dumbphone for your smartphone.
But, there are a couple new additions to the accessory lineup. The most interesting is the new Dot View case, which will show old school style dot notifications for time, weather, and caller ID, even when the case is closed. This means that you can get info without having to unlock your device, or even open the flip cover. There is also a new BoomBass Bluetooth speaker cube, which is said to be small enough to fit in your hand, and offers NFC tap-to-connect. It should offer somewhere between 6 and 9 hours of music playback between charges.
No word yet on pricing for the new accessories, but considering the original Flip case was priced at $39.99, we'd expect the Dot View case to be a bit more expensive than that. *Update* The Dot View case has arrived on HTC's website and it is listed at $50, but it isn't available for purchase just yet.