As stated earlier, the chip packing has moved from wire bonding to flip chip. So what's the big deal? Wire bonding is exactly as it sounds - the die connections to the board interconnections (pins or "balls") on the bottom of the packaging are tiny little wires. Although this process is generally cheaper than flip chip, there are issues with it. Firstly, if the chip is going to have many I/O signals, it is going to need a lot of interconnects. This means that the wires will have to be narrower in order to pack more in, reducing their strength and increasing their resistance.