[Cooker] About Nautilus and about Kernels

[Claudio]

Hi all!
I've seen that nautilus in cooker tree is still 0.5 while version 0.8 is out 
with many improvements... Is there any reason to keep the old version?
The other thing: why do we have 2.2.18 and 2.4.0? Which one will be used by 
default?

        Claudio