The sunshield of Gaia, also called the Deployable Sunshield Assembly (DSA), stands a little bit naked in a cleanroom of the ESA/Arianespace launchbase in Kourou after it was unpacked from its transport container. All the Multi-Layer Insulation was removed for inspections and needs to be reinstalled. This was reported in the latest blog post of the ESA Gaia launch blog http://blogs.esa.int/gaia/2013/09/17/from-vs-07-to-vs-06/ . Additionally it was stated that for the launch of Gaia the launcher will be used that was intended to be used for the now delayed launch of the O3B satellites. Thus, the launcher designation was switched from VS-07 to VS-06. The payload fairing remains the same as Gaia will need a special wider version of the fairing. If the Fregat upperstage will also be switched is currently unknown.
Update: ESA has confirmed that the Fregat upperstage will be switched, too.