News from z~6-10 galaxy candidates found behind gravitational lensing clusters

6 pages, figs included. To appear in "At the Edge of the Universe: latest results from the deepest astronomical surveys", Eds. Jose Afonso, Henry Ferguson and Ray Norris, ASP Conf. Series, in pressWe summarise the current status of our project to identify and study z~6-10 galaxies thanks to strong gravitational lensing. Building on the detailed work from Richard et al. (2006), we present results from new follow-up observations (imaging) undertaken with ACS/HST and the Spitzer Space Telescope and compare our results with findings from the Hubble Ultra-Deep Field (UDF). These new observations are in agreement with the high-z nature for the vast majority of the candidates presented in Richard et al. (2006). We also discuss the properties of other optical dropout sources found in our searches and related objects (EROs, sub-mm galaxies,...) from other surveys