Over the past week or so I have been doing a lot of background research and exploring some of the existing solutions.

This project has the advantage of working from existing commercial solutions. No point re-inventing the wheel or sprocket feeder in this case...

Commercial Units:
Mechanical - Some older units utilise a series of mechanical linkages to increment the tape when a bar above the unit is actuated from the picking head.
Electrical - Modern units make use of cheaper electronics to advance the tape with electric motors. Styles vary drastically, all of them spool the cover strip in some manner then let the empty tape dump onto the floor. Electronics allow for smarter systems with feedback to the controller and additional information.
Drag - Very cheap machines like the TM220A utilise the picking nozzle to advance the tape.

Mechanical Systems:
Advantages - Simple, fewer parts to fail, long life span with metal construction
Disadvantages - Complex to design, high tolerances required for manufacture, no feedback, fiddly to 

Electrical System:
Advantages - Significant system feedback on feeder state, Chip counting, easily adapts to different components
Disadvantages - Mechanical and electrical design required, reliable common sources of compact motors difficult

Existing DIY designs

There are very few examples of open soruce designs. Most people with advanced openPNP projects are using commercial feeders found on eBay or similar. This is the only example I was able to find of existing works http://tim.cexx.org/?p=803

There are existing threads on diy PNP systems http://www.eevblog.com/forum/chat/better-pick-and-place-machine-diy/ This thread specifically makes mention of feeders being the most critical component of an open PNP system.

Vibrating chip feeders have also been developed however they have none of the design challengs that a tape dispensor has. http://www.briandorey.com/post/DIY-Pick-and-Place-V2-Vibratory-Chip-Feeder.aspx