`ipython profile` prints profile help

also fix typo introduced into ipcluster

IPython/core/profileapp.py

@@ -207,4 +207,14 b' class ProfileApp(Application):'
         create = (ProfileCreate, "Create a new profile dir with default config files"),
         list = (ProfileList, "List existing profiles")
     ))
+    
+    def start(self):
+        if self.subapp is None:
+            print "No subcommand specified. Must specify one of: %s"%(self.subcommands.keys())
+            print
+            self.print_description()
+            self.print_subcommands()
+            self.exit(1)
+        else:
+            return self.subapp.start()
 

IPython/parallel/apps/ipclusterapp.py

@@ -426,8 +426,9 b' class IPClusterApp(Application):'
     
     def start(self):
         if self.subapp is None:
-            print "No subcommand specified! Must specify one of: %s"%(self.subcommands.keys())
+            print "No subcommand specified. Must specify one of: %s"%(self.subcommands.keys())
             print
+            self.print_description()
             self.print_subcommands()
             self.exit(1)
         else:
@@ -435,7 +436,7 b' class IPClusterApp(Application):'
 
 def launch_new_instance():
     """Create and run the IPython cluster."""
-    app = IPBaseParallelApplication.instance()
+    app = IPClusterApp.instance()
     app.initialize()
     app.start()