gecko
                                        - float
                                    
                                    
                                            Gecko engine revision number.  Will evaluate to 1 if Gecko 
is detected but the revision could not be found. Other browsers
will be 0.  Example: 1.8
                                    Firefox 1.0.0.4: 1.7.8 <-- Reports 1.7 Firefox 1.5.0.9: 1.8.0.9 <-- Reports 1.8 Firefox 2.0.0.3: 1.8.1.3 <-- Reports 1.8 Firefox 3 alpha: 1.9a4 <-- Reports 1.9
webkit
                                        - float
                                    
                                    
                                            AppleWebKit version.  KHTML browsers that are not WebKit browsers 
will evaluate to 1, other browsers 0.  Example: 418.9.1
                                    Safari 1.3.2 (312.6): 312.8.1 <-- Reports 312.8 -- currently the latest available for Mac OSX 10.3. Safari 2.0.2: 416 <-- hasOwnProperty introduced Safari 2.0.4: 418 <-- preventDefault fixed Safari 2.0.4 (419.3): 418.9.1 <-- One version of Safari may run different versions of webkit Safari 2.0.4 (419.3): 419 <-- Current Safari release Webkit 212 nightly: 522+ <-- Safari 3.0 (with native SVG) should be higher than thishttp://developer.apple.com/internet/safari/uamatrix.html