We are putting together the program now, its looking strong.
I am not completely aware of the process / workflow you are using for this. and how suggestions get selected . From my personal point of view I would be ready to offer some topics myself.
Bitcoin - How I understand it: My high-level conceptual understanding of the Bitcoin mechanism after having read and documented the entire reference client code for myself. 45 minutes, tutorial style.
An Analysis of Bitcoin Anonymity: To which degree is Bitcoin really anonymous? How do Bitcoin usage patterns affect anonymity? What can be done to improve Bitcoin anonymity? How can Bitcoin payment flows can be traced? 30 minutes, talk, describes work-in-progress (and will contain first results when applying our analysis algorithm to the current block chain).
Improving Bitcoin Wallet Security: How can we split the authorization phase in the Bitcoin mechanisms to two machines in such a manner that compromising ONE machine does not result in money being stolen? Which crypto possibilities are there? Which solution are we in the process of implementing? 30 minutes, talk, describes work-in-progress (currently at the stage of starting to work on the selected embedded hardware)
Bitcoin Todo List: Critical remarks on the state of development in Bitcoin. What must be done (and at which level or priority) if Bitcoin shall become a success any time soon. 20 - 30 minutes, could be part of a brainstorming session or panel discussion.
I am not sure what fits the conference mode best and how things get organized there - as I am more used to the traditional ol' style of "over"organized conferences with submission deadlines and schedules and stuff. Just post what suits you best.
To give you an idea on myself: I have been regularly lecturing in class and giving industry talks for the last twenty years or so. Currently I am hacking on a forked version of the reference client to which I added some 1.000 lines of code and I am supervising two students working on Bitcoin related topics.
I am dependent on the precise schedule of the program, because I have to match some time & travelling constraints. "Just come and see" will not work for myself (besides being detrimental to the possibility of preparing something).
I can provide more details on my suggestions above.