The LM339 is rated to 36V, but that doesn't really matter since you'd run it off the FET gate voltage source (8-12 V per the disucssions above), and anything over 20V Vgs is going to kill most FETs anyway. The 339 will also sink 20 mA, which isn't a lot, but seems comparable to previous designs (an AVR I/O pin or a '244 pull-down / 10K resistor pull-up). None of these solutions will work nearly as well as a dedicated monolithic gate driver IC (which will pretty much need no additional components besides bypass caps), but are generally less expensive and the parts are more readily available. In high volume, the gate driver ICs are probably competitively priced, and seem like the way to go if you want fast turn on/off times. Be careful what you wish for, however, as fast turn-off will create huge dI/dT spikes and requires good protection of the FETs (and will be dumping lots of power into your protection diodes). I would actually recommend a series gate resistor and the option to add a Miller capacitor to control the output slew rate if you use a real driver IC capable of sourcing and sinking amps of current into the gate capacitance.
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