Spotting Scope or Binoculars?

I have spent the last month in my garden (well, when there hasn't been cloud
cover) with a pair of old 7x50 binoculars and a starchart. Mainly finding my
way around the constellations, and roughly locating the Messier objects. I'm
in a light-polluted area so can't resolve much detail (I need to arrange a
trip to a dark site one of these days!)

At this point I want to get a new pair of binoculars or a spotting scope
(the 7x50's are borrowed) I've spent some time reading reviews and forums
looking for the best options for a new pair of binoculars - And I can't
decide between getting binoculars or a spotting scope. I've narrowed it down
to the following; (It's just coincidence that they're all Nikon - honest!)

- Nikon 12x50 Se cf binoculars (I assume these are Superior E) 780 euro
- Nikon 10x42 Se cf binoculars 720 euro
- Nikon spotting scope 80A
http://www.nikon.co.jp/main/eng/news...ope80_e_00.htm 515 euro (with
20-60 zoom)

Binocular advantages:
Using 2 eyes, not one - how much difference does this really make?
Binocular astronomers love the Nikon Superiors!
Robust
General purpose use, take them anywhere
Easier to hold than a scope (?)

Scope advantages:
80mm aperture versus 50mm in the binoculars
20-60 zoom (don't know how useable the 60 zoom would be, wouldn't this give
a *very* small exit pupil?)
Robust, rubber coated
Can take various lenses, and possibly camera adapter (almost a small
refractor telescope)
Cost less (although not really a prob if the binocs would be a better
choice)

I haven't read much about scopes in this newsgroup. Do people generally
favour binoculars for astronomy? I've looked at Zeiss, Swarovski, and Leica
as well. Leica Trinovids are another option, although this would be pushing
the price up even more, and I think I'd be happy with the Nikon Superiors.
If you had 700 euro burning a hole in your pocket, which one would you buy?

One last question, what is 'eye relief' ? What effect does it have when
you're using a scope with poor eye relief?

Thanks,
John.