Chelsea's opening price for Jackson looks ridiculously high, but i have understand it. They're so good in doing football business, and may be welcoming any offer that's less than it. They bought him for around 30m, and pretty good enogh if they can flipping him for 100% profit.
Apart from that, Jackson developed well since he came from Villareal. He's still very young as a striker,'and has so much potential. That may be a reason why his club putting 100m as his price. Even if there will be a club demand him, i'm sure that club will be surely negotiating and prefer to reduce his fees.
Let's see what club that has interest in him. The latest news suggest MU and Villa, but prefer to see him moves to the MU.

It really funny reading that United is interested in signing Jackson. I just hope this is not true because of all the strikers in the world, they couldn't see any to sign but "Chelsea's reject"?
If they cannot sign a better striker because of lack of european football and limited funds, they should just stick with the ones they've got or go for Watkins instead of signing Jackson.