At the moment for iOS 5 and iOS 5.0.1 only tethered jailbreak solution available but if you want to have untethered jailbreak on your iDevice then you can downgrade it to iOS 4.3.3 from iOS 5 or later.
Through guide below you will learn how to downgrade to iOS 4.3.3 from iOS 5.0.1 or iOS 5.
Downgrade iOS 5.0.1 or iOS 5 to iOS 4.3.3
Put your iDevice into DFU mode
Verify that your Hosts file is devoid of any Apple references
Launch RedSn0w and click “Extras” > “PwnedDFU”
Launch TinyUmbrella and click “Start TSS Server”
Launch iTunes, hold down “Shift” key + “Restore” button (Windows) or “Option” key + click “Restore” (Mac) and select downloaded iOS 4.3.3 firmware file
If you find “Recovery Error” message just close iTunes
Launch TinyUmbrella and click on “Advanced” and deselect “Set Hosts to Cydia on Exit…” and close down TinyUmbrella
Launch RedSn0w and choose “Extras” > “Recovery fix” and wait for a while
Again launch RedSn0w and choose “Extras” > “Just boot” and wait until process gets complete
Activate your iDevice through iTunes
Done! Your iDevice is now back on iOS 4.3.3.
You can share your experiences of the implantation of above process to downgrade to iOS 4.3.3 from iOS 5.0.1/iOS 5 in comments section.