added debounce to 'latest' filter

lib/node.js

@@ -2,6 +2,7 @@ var web3 = require('ethereum.js');
 var _ = require('lodash');
 var os = require('os');
 var shelljs = require('shelljs');
+var debounce = require('debounce');
 
 var Primus = require('primus'),
 	Emitter = require('primus-emit'),
@@ -386,7 +387,9 @@ Node.prototype.setWatches = function()
 
 	this.chainFilter = web3.eth.filter('latest');
 	this.chainFilter.watch(function(log) {
-		self.update();
+		debounce(function() {
+			self.update();
+		}, 50);
 	});
 
 	this.updateInterval = setInterval(function(){