Except for the color, the BC700 looks exactly the same as the better-known BC900. However, it is actually a "handicapped" version of the old charger. Its charging current can only go up to 700mA in three steps (200/500/700). The BC900, on the other hand, can go up to 1000mA for 4 cells, or 1800mA for 2 cells. Also the BC900 package includes eight NiMH rechargeable cells (4 AA and 4 AAA), eight C/D cell adaptors, and a carrying case. The BC700 does not come with any bonus items.
This is not to say that the BC700 is a bad product. Quite the contrary, it is better than any other NiMH AA chargers in the market except for BC900 and Maha MH-C9000. If you can find it at a substantial saving (like maybe 30% off from the price of BC900), it is still a good buy. But as it is right now, I recommend getting its older brother instead.