With regular flourescent lights i do not think you will generate much heat.
But this raises questions:
Is the fixture going to be inside a hood?
if yes then a vent without a fan will probably be fine
if no then you should be fine
How far away from the top will the fixture be:
This will change the temps and will need to be monitored. You will have to find what works best for you. The closest as possible without raising the temps to much. In the winter you may want to have it closer to raise the temps.
With the CF lights yes i feel a compueter fan is a must especially if its in an enclosed hood.
And do your self a favor and buy a digital temp/humidity guage with a remote humidity sensor.
www.drfostersmith.com has them the little analog ones do not work well and give false readings. The remote sensor part is a must if you want the guage to last, the humidity destroys the electronics.