One interesting perception I've found in World of Warcraft lately is that unless an item is level 70, its less than adequate. I've encountered this attitude in guild chat, trade chat and even general chat. Somewhat staggering as some of the best trinkets are from BWL, a level 60 instance.
However there is one outstanding trinket I'd like to bring your attention to, which is a level 60 epic:
With the nerf of three piece Stormrage and Transcendence bonuses, mana regeneration perhaps one of the most important stats as a healer. Its this stat which allows us to keep healing over a long time, and a trinket like this is very useful for long fights and for healers who are constantly in the 5 second rule (hello 3 stack lifebloom!). Its also quite hard to judge the effectiveness of proc based items, but hopefully my calculations below will make it easier.
Taking my stats from last nights Karazhan run (finishing off Netherspite, Prince and Chess), I can see that my Blue Dragon card procced 14 times over 33 minutes of healing. Unfortunately the Armory hasn't updated in a while, to see either of my two new helms Cowl of Natures Breath or Crown of Malorne, but I had 684 spirit fully buffed with Divine Spirit last night.
You can calculate the mana regained each proc as shown below:
Spirit formula for druids in caster form/moonkin/tree is: Spirit/4.5 + 15
684/4.5 + 15 = 167 per tick (2 seconds) * 7.5 (to get 15 seconds worth of mana regeneration)
Giving us a total of 1252.5 mana regained per proc
Using the data from the log above, 33 mins is equal to ((33 * 60) / 5) 396 five seconds intervals:
(14 * 1252.5) / 396 = 44.3 mana/5 throughout the run last night.
44.3 mana/5 is a substantial amount for any trinket, and is quite easily obtainable.
So still a very useful trinket for Tree of Life druids who have a good amount of spirit and are in the 5 second rule a lot of the time.