Well, iOS 6.1.3 is available for all the iPad, iPhone and iPod users and as they mentioned they have corrected the security flaws but still the screen lock bypass bug which they mentioned to be corrected is still there on the phone. Take a look at the video mentioned below to see that security flaw working in detail, you will just have to initiate the call by voice and then eject the SIM of that phone and then after few steps, you will be taken to the contacts screen bypassing the security code on that phone.
They have recovered many security flaws out of them they have given the credit to the team named as evaders (which was responsible for creating the jailbreak application named evasion). Some of the exploits which were used by evasion (the jailbreaking tool) have been patched so now you will not be able to use to for jailbreaking your iPhone, iPod or iPad. Moreover, Apple has not stopped signing in of iOS 6.1.2, so you will not be able to downgrade your device also.
But evaders claim that they still have some exploits in their reserve and they were already prepared of this step taken by Apple. So, you will be able to see the jailbreak tool again in future. Moreover the Apple device with A-4 chip can still be jailbroken but (in tethered way) with the help of the latest version of Redsnow.
Apart from these security flaws I cannot see much change in the battery backup which was promised to be improved after getting rid of the Exchange Calendar bug. Well, I hope that Apple will into this major security flaw and release another upgrade for this bug. Another thing apart from fixing the bugs is that the Apple has also improved the maps in Japan.