most of the cost is in the nand, so the 330 probably uses asynchronous or lower endurance nand (this is what kingston did with their new hyperx 3k ssd's), or both.
The 330 Series have now officially launched. And with that comes the authoritative answers:
http://techreport.com/discussions.x/22801
So basically as speculated before, it is a significantly cheaper 520 with lower grade flash chips.
According to The Tech Report, it will not replace the 320 Series in the market.
