README.md in futuroscope-0.0.2 vs README.md in futuroscope-0.0.3

@@ -39,10 +39,11 @@
 
     $ gem install futuroscope
 
 ## Usage
 
+### Simple futures
 ```Ruby
 require 'futuroscope'
 
 x = Futuroscope::Future.new{ sleep(1); 1 }
 y = Futuroscope::Future.new{ sleep(1); 2 }
@@ -53,10 +54,33 @@
 
 puts x + y + z
 => 6
 ```
 
+### Future map
+```Ruby
+require 'futuroscope'
+
+map = Futuroscope::Map.new([1, 2, 3]).map do |i|
+  sleep(1)
+  i + 1
+end
+
+puts map.first
+=> 2
+
+puts map[1]
+=> 3
+
+puts map.last
+=> 4
+
+# This action will actually only take 1 second.
+```
+
+### Convenience methods
+
 If you don't mind polluting the `Kernel` module, you can also require
 futuroscope's convenience `future` method:
 
 ```Ruby
 require 'futuroscope/convenience'
@@ -66,9 +90,33 @@
 z = future{ sleep(1); 3 }
 
 puts x + y + z
 => 6
 ```
+
+Same for a map:
+
+```Ruby
+require 'futuroscope/convenience'
+
+items = [1, 2, 3].future_map do |i|
+  sleep(i)
+  i + 1
+end
+```
+
+## Considerations
+
+You should never add **side-effects** to a future. They have to be thought of 
+like they were a local variable, with the only outcome that they're returning a 
+value. 
+
+You have to take into account that they really run in a different thread, so
+you'll be potentially accessing code in parallel that could not be threadsafe.
+
+If you're looking for other ways to improve your code performance via
+concurrency, you should probably deal directly with [Ruby's
+threads](http://ruby-doc.org/core-2.0/Thread.html).
 
 ## Ideas for the future
 
 * Having a thread pool so you can limit maximum concurrency.