bluetooth module for arduino uno

Hi, I am new to this.I want to connect to arduino via bluetooth. Is all hardware required is one slave bluetooth module like this one -

http://www.ebay.co.uk/itm/115200bps-Bluetooth-Module-Slave-Wireless-Serial-Port-fr-Arduino-Balance-Robot-/320811073519?pt=UK_AudioElectronicsVideo_Video_TelevisionSetTopBoxes&hash=item4ab1d47fef

or do I also need a usb to serial port converter also like this one -

http://www.ebay.co.uk/itm/Bluetooth-Module-USB-6Pin-Serial-Port-Adapter-fr-Arduino-Self-Balance-Robot-/320811073570?pt=UK_AudioElectronicsVideo_Video_TelevisionSetTopBoxes&hash=item4ab1d48022

I don't mind if the default bluetooth settings work ok. Thanks.

I hesitate to answer because I'm not remotely sure what the answer is, but I have been playing with my bluetooth shield for a bit now, and communicating with the arduino normally over bluetooth doesn't seem to be a problem. My problems are with avrdude and doing uploads via bluetooth. You can read what I have learned about my shield here:

http://home.comcast.net/~tomhorsley/hardware/arduino/arduino.html