If the +680 Weapon Damage does actually equate to what is referred to as the Weapon DPS stat then UHW should be absolutely amazing for Ferals, if it equates to Low/Top End Weapon Damage I am unsure how it would react.
I am currently using Tia's Grace and Fluid Death. According to Mew and a few layouts of Feral Trinkets and their values for my gear level, Tia's Grace is better than every other 359 currently on Live. If Unheeded Warning's buff is what I think it is, it should be the top BiS trinket, pre-Heroic Raids (i.e. 372 Trinkets)
These numbers were logged from the PTR with the Buffed version of UHW by Leafkiller in this link: http://elitistjerks.com/f73/t110352-feral_cat_cataclysm_release/p6/#post1848569
Fluid Death + Tia's Grace: 20,828
Tia's Grace + Unheeded Warning: 20,853
Fluid Death + Unheeded Warning: 21,070
Does anyone else have any other substantial numbers to bring to the table to take a look on this trinket's future in Kitty Gear??