Glad you posted the questions. I'll contribute to #4 here.
You should enter the lottery in February -- click on the 2010 Whitney Permit Availability on the left above and follow the links, especially the lottery progress thread.
If you have enough $$, maybe submit several lottery applications (just be aware that if more than one is successful, there are NO refunds.) Get together with your group and decide what dates you are all willing to commit to hiking Whitney, then submit your lottery application in February. Note that weekends fill up most quickly, and giving more dates may help your chances.
Also, understand that when you hike Whitney, it is a very good idea to go to the area two days before the hike to acclimate. It is highly likely that someone in your group will be affected by the high altitude that they won't make the summit if you don't spend more than 24 hours above 8000' before the hike. Staying at 10k (Horseshoe Meadows) is best. So try to add that acclimation time into your plans.
For reference, here is the 2010 lottery application form:
NOTE: DO NOT USE these to try to apply for the lottery or for a Wilderness Permit outside of the lottery.
These are out-of-date and NOT VALID!!!
