Well from speculations. Tinker..seem to have a "Spell Research" level caps.
Other Trade Skills does not seem to have level cap. Fishing has a Level
Cap similar to Melee level cap (Level*5)+5...

Spell Research seem to follow...level 16=50...then +5 on every level there
after. (anyone know the actual formula?)

Bertoxx server

Another thing found, I was checking out the guy (dwarf) that give out the
quest for Dragon Scale Armor in Rathe Mtn. (Inn near the Lake Rathe zone).
Well, there's a gnome next to him who sell gems..(never seen him before).
IF you hail this gnome, he talk about better stones and stones cutting (gem
cutting). Well that seem to relate to the new tinker item GEM Cutter. So
any info, you guys can give...(He won't say much about it.)

-Untos Gnomish Enchanter.