Personally I don't see any reason NOT to use Adobe RGB if you know you're going to commit to shooting RAW and doing post' since it does have the broader spectrum of the two.I have decided i need to get back to shooting raw,I see you can choose sRGB or Adobe RGB,would the decision as to which one be effected by the choice of software you where going to edit in, i think I used sRGB in the past.
If your destination for all you images is the internet, then sRGB may be your best bet. If you're hoping to make prints someday then Adobe RGB would be the color space to use.