Travel, shooting action such as dogs running, playing, low light situations

I'm an amateur although I do take many photos!  I would love to take a camera everywhere with me and sometimes when I travel I want to take great shots (in low light) or spur of the moment but dont' want to lug my heavy SLR or take my expensive kit out in a busy market place.  I've been told by all canon peeps to get the Canon G10 (!) but I am a Nikon gal and did love my old coolpix5000 I had a few years ago.    Should I get the Nikon or G12? G10? G11?  So confused!