ORA prices are volatile as the US$ is. :-( & :-)
But more interesting in fact are newer offers alike "lion.cc" who attempt to undermine the price fixing for books (yeah, we have, don't forget the german ambitions).
However all of the above turns out, I still prefer to go to a well sorted book store, where they have all ORA and all Addison Wesley. And there I hang out and read and buy the books I need. :-)
E-commerce is something quite nice, but can't replace well working and comfortable procedures in all places. Hmm, may be I should ask for rebate or perhaps a coffee next time {grin}

Have a nice day
All decision is left to your taste