As many of you may have heard, Apple's new iOS 9 is "rootless", which supposedly would make jailbreaking much more difficult. However, it has been shown to be possible. ih8sn0w posted a youtube video of his jailbroken iphone running iOS 9 and even gave some hints about it in the video description section. However, he also stated that he will NOT be releasing it to the public. So it would be quite the feat and adventure to take his hints and comments and use that to figure out how to jailbreak iOS 9, as Pangu and TaiG (the teams that jailbroke versions of iOS 8) have nothing released as of yet. There is a partial jailbreak that downloads a separate app store that works on iOS 9, but they request that you send a donation to them in order to get Cydia, which sounds rather fishy.
Here are the hints/comments that he put into the description:
Poking into iOS 9 is fun. A little annoyed at some new things. But very surprised at how similar it is to iOS 8 internally.
Worth noting, iOS 9+ arm64 iDevices now enforce a checksum on _TEXT/DATA.const regions of the kernel through the use of TrustZone. Modifying said sections will cause the device to panic (either at kernel or EL3 will force a reboot if the kernel refused to gracefully panic). Essentially, it's KPP (Kernel Patch Protection). You can race it though if you want to play with things. Just be quick! ;P
Also, there should technically now be two additional partitions (baseband_data s1s3 and logs s1s4) but didn't really bother with those as they weren't critical.