a few comments with more info
and links I found helpful

.toInt is no loger present in Swift 2

.None behaves differently than was documented
the following compiles just fine:

var foo = 4
if foo != .None
{
  "something"
}

however, this does not compile:

if foo != nil
{
  "something"
}

countElements is no longer available
in Swift 2.0, use str.characters.count

iterating thru characters in a string is now:
for character in str.characters

enumerate(shoppingList) ->
shoppingList.enumerate()

deleted a section on scoping, since it was referenced correctly later (line 79)
println -> print
when iterating over a string, use str.characters
do { } while -> repeat { } while

'#' has been removed from Swift; 
double up to make the argument label the same as the parameter name

to omit an external name for the second or subsequent parameters of a function, 
write an underscore (_) instead of an explicit external name for that parameter

also fixed some typos

before the text said the property was nil
which it wasn’t, not sure how it was supposed to work
so I made up a new example which illustrates the behavior

odd that Color and SurveyQuestion2 ever worked
default initializer also appears to work differently
adjusted comment and added example to illustrate
  how default values are initialized

adjusted comment to reflect that, since 
the bank’s coins print correctly at the end

@objc no longer required for 
testing protocol conformance with ‘is’ and ‘as’

plus added one simple example

&/ and &% removed in Swift 1.2