I think BD hitting 200k is near a certainty, even without Trusty Bell.
Blue Dragon sold 693 copies last week, and is only 11,470 units away from hitting 200k LTD.
This might seem like a lot of units to cover, since it's only selling 700 a week. However, BD has done well when 360 hardware has done well. 1 month ago, it sold 1800 in one week when the 360 sold 3,500 units due to Golden Week.
Thats a 60% decrease over 4 weeks - not bad considering the X360 hardware dropped 40% in sales in the same period. One would say it doesn't bode well.
But then you check early April, and Blue Dragon was selling 1,200 per week.
So after everything's said and done, since April, sales have decreased a mere 600 units/wk in 2 months. That's pretty good. Add in the fact that Trusty Bell could move 5,000 hardware units (at a very very low prediction), and we should see Blue Dragon hit 190,000 units LTD easy, or even 192,000~193,000. So it only has to move 7,000 units for the rest of it's life.
Honestly? I'll go out on a limb and say that Blue Dragon has enough gas in it (provided Trusty Bell moves 10,000 h/w units or more, and keeps the 360 sustained for a month before it goes down to 2,000 h/w a week), to reach 210,000 at a minimum, and even hit 225,000 at the end, as it should get a strong increase when Lost Odyssey launches.
A 50/50 over/under ratio for Blue Dragon is somewhere at 210~215k (50/50 chance it breaks 215k), atleast in my estimation. It's had a great run thus far, and sales have proven via Golden Week, that when hardware sales boost, so does Blue Dragon's sales.
A final example:
Blue Dragon's VGChartz ranking in 2/18/2007: #84
Blue Dragon's VGChartz ranking in 6/03/2007: #122
Dropping 40 places in 3 and 1/2 months is nothing short of amazing for an RPG.