Just skimmed through Marc Tuters's follow up to open plan. Marc gives a great summary of what has being said + some other comments about his chat with conference-goers; which is nice since it adds some stuff to the huge amount of material I gathered from there. I particularly agree with his take about current locative media projects:

A common criticism that arose in my discussions with other conference-goers regarded the perceived lack of diversity amongst Locative Media projects. While a few visionary art works generated some buzz (...), the field of Locative Media that emerged from this discourse-driven event seemed best expressed by two particular projects: Urban Tapestries and Blast Theory.

How to move further from both the 'post-it' thing and the participants tracking?
Besides, Marc now runs Locative Media News on this MUSE platform.