wrote:
Can someone explain to me what exactly nitro means. Are they
injecting
nitrogen into the beer?

basically, yes, the beer is driven to the bar using a mix of nitrogen &
C02, both are dissolved into the beer, AFAIK Guinness invented it (&
other Stout brewers followed suit.

In the 1990s, in the UK at least, nitrokeg ales such as Boddingtons,
Caffreys & John Smith's cropped up with terms such as creamflow,
smoothflow, etc, but they were simply fairly dull ales served in this
manner.

How is it different from the same beer "on tap"?

Well, they're both "on tap", but the nitrogen helps to form a lasting
creamy head, and as less C02 is present, the beer might not have the
"bite" that C02 alone can give & it should feel less gassy than if it
was just served under C02 alone (the normal method of dispense for keg
beer).

IMO some beers suit nitro better than others - stout does just seem to
work, but otherwise I'm not a big fan of nitrobeers, it seems to deaden
the flavour & the creamy mouthfeel is a bit of a one-trick pony.

Though I am curious to try some decent beers in nitro form for
comparison, I can only think of 1 or 2 UK craft-brewers that do
nitrokeg their stout or any beers. This is probably down to the
peculiarities of the UK pub beer market where almost all of the
domestic-brewed quality beer is served as cask beer.

Why does the same beer taste so much better when its on tap as
compared
to bottled? is it a freshness thing?

yes, probably - most bottled beer has gone thru more processing than
draft/draught beer (filtering, pasteurisation, etc) & possibly been
hanging around longer too (I've heard over here that supermarkets have
asked for 15 & 18 months shelf-life, many beers are not going to be
tip-top by then)

Thanks for all the helpful (and even not so helpful) answers
everyone.
drinkin oatmeal stout

had some great cask beers this week, including a top-notch stout from
E&S, Yorkshire; at one of UK's best beer pubs, Ship & Mitre, Dale
Street, Liverpool (www.shipandmitre.co.uk - I think)
cheers,
MikeMcG.