Update the README

README

@@ -1,71 +1,52 @@
-== Money class
+== Money
 
-This money class is based on the example from the ActiveRecord doc:
-http://api.rubyonrails.org/classes/ActiveRecord/Aggregations/ClassMethods.html
-
-Its in production use at http://www.snowdevil.ca and I haven't found any major issues
-so far. 
-The main reason to open source it is because It might be useful to other people and 
-I hope i'll get some feedback on how to improve the class. 
-
-I bundled the exporter with the money class since some tests depend on it and I figured
-that most applications which need to deal with Money also need to deal with proper 
-exporting. 
+This library makes it easier to deal with Money values, storing them as integers to avoid floating-point math errors.
 
 == Download
 
 Preferred method of installation is gem: 
 
-  gem install --source http://dist.leetsoft.com money 
+  gem install --source http://gems.github.com collectiveidea-money 
 
-Alternatively you can get the library packed
+You can find the source at:
 
-  http://dist.leetsoft.com/pkg/
-
-== Usage
-
-Use the compose_of helper to let active record deal with embedding the money
-object in your models. The following example requires a cents and a currency field.
-
-  class ProductUnit < ActiveRecord::Base
-    belongs_to :product
-    composed_of :price, :class_name => "Money", :mapping => [%w(cents cents) %(currency currency)]
-
-    private        
-      validate :cents_not_zero
-
-      def cents_not_zero
-        errors.add("cents", "cannot be zero or less") unless cents > 0
-      end
-
-      validates_presence_of :sku, :currency
-      validates_uniqueness_of :sku        
-  end
+  http://github.com/collectiveidea/money
 
 == Rails
 
 There is a rails extension that makes it easier to store money values in the database.
 
   class Product < ActiveRecord::Base
     money :price
+    validates_numericality_of :price_in_cents, :greater_than => 0
   end
 
 This assumes that there is a price_in_cents (integer) column in the database, which can
 be changed by passing the :cents option.  You can also specify the :currency option to
 save the currency to a field in the database.
 
   class Room < ActiveRecord::Base
-    money :rate, :cents => :rate_in_cents, :currency => :rate_currency
-    money :discount, :cents => :discount_in_cents
+    money :rate, :cents => :rate_cents, :currency => :rate_currency
+    money :discount, :cents => :discount_cents
   end
 
-You can pass a String, Fixnum, or Float as a parameter to the setter, and it will call 
-#to_money to convert it to a Money object.  This makes it convenient for using money
-fields in forms.
+You can set the attribute to a String, Fixnum, or Float and it will call #to_money to
+convert it to a Money object.  This makes it convenient for using money fields in forms.
 
   r = Room.new :rate => "100.00"
   r.rate  # returns <Money:0x249ef9c @currency="USD", @cents=10000>
 
+By default, money values will be stored with a precision of 2 (cents). If you need to store different precisions, such as to the nearest tenth of a cent, you can specify the +:precision+ option:
+
+  class Room < ActiveRecord::Base
+    money :rate, :precision => 3
+  end
+
+  r = Room.new :rate => "100"
+  r.rate.format  # returns $100.000
+  r.rate = "100.995"
+  r.rate.format  # returns $100.995
+
 To use the Rails functionality, install money as a plugin, or require 'money/rails'.
 This version is compatible with Rails 2.2.  For compatibility with previous versions of
 Rails, check out the rails-2.1 branch.