I don't know if we're the intended audience for this sort of thing. By and large, we're already familiar with the good players in our system, since we haven't had anything else interesting on which to focus over the past eight months. Nevertheless, the wise and vitreous Conor Glassey has come out with his list of the top 10 Mariners prospects for Baseball America, and I think it's worth your taking a look. (h/t JY)
I'll try not to spoil too many of the surprises, but I will take this opportunity to urge all of you to remember the name Johermyn Chavez. Chavez turns 22 in January and is a long way away from the Majors, but one absolutely must bear in mind that Brandon Morrow wasn't traded for Brandon League straight-up. There was a young prospect who came over as well, and the prospect's stock is only higher now than it was when the got him.
Does Chavez have tremendous bust potential? He most certainly does, and his 2010 numbers were inflated by hitting in High Desert, where games are played at an elevation that half the world away is referred to as the Death Zone. But for those of us who are frustrated with League's lack of progression, Chavez kind of gives the trade another chance.
The rest, I'll leave up to you to peruse. All prospect lists are subjective and there's no way of knowing whether Taijuan Walker is actually a better prospect than, say, Mauricio Robles, but worry less about the rankings and more about the information and the chance to discuss.