People feel better about buying something on sale because they think they are getting a good deal. It's psychological. However, prices can vary from sale to sale, season to season.
For example, department stores tends to markup prices after Thanksgiving for the Christmas season. Therefore, even with the same percentage discount, some items will be more expensive during Christmas than during Thanksgiving.
The real discount will likely not happen until next year when Lenovo wants to sell off their remaining stock of Y580s to make way for an updated version using Intel's Mobile Haswell CPU.
Ive done over 60 hours of research about a gaming laptop in the range of a gt 650m ---- gtx 670m (literally like 60 hours, its become an addiction) i will tell you that the Y580 with FHD, blu ray, etc, is the best price BUT the only thing i dont like about it is the Glossy screen. Personally i prefer Matte. Also just the other day there was an offer for an ASUS G75VW (i7 3610qm / gtx 660m FHD (Matte) for $1000 but it sold out fast
so to sum it up, its a great deal for the specs but it depends on your preference of glossy vs matte display and if you wait for blackfriday/christmas deals you can get other laptops at the same price or cheaper or u can even get the Y580 maybe around $750-800 (FHD Model) and never get a 1366x768 display