1) Manual vs Auto Batteries - When I ordered my first pv, I was convinced it needed to both look like a cigarette, and be automatic. It turns out I prefer manual batteries, and it doesn't need to look like a cigarette at all! This will obviously vary from person to person, just like all aspects of vaporizing, however, from my reading, it seems that manual batteries are by far more popular than autos, even among those who thought they would need a auto.
2) The size will directly correspond to battery life. The bigger it is, the longer the battery will last. In my opinion, more battery life is better. The less often you have to change/charge batteries the more convenient vaporizing will be, and the more convenient it is, the easier it will be to stay avoid cigarettes.
3) Flavors will depend entirely upon you. I have tried several flavors so far, and the only ones I can vape for more than 20 minutes or so are the tobacco flavors, and sometimes the coffee flavors if I'm in the mood. I haven't yet found a fruity/candy flavor I actually like. However, many people love the fruit/candy flavors. So you will pretty much have to try them yourself. Same for nic levels. I find 18-24mg/mL perfect most of the time, but first thing in the morning and right before bed I vape 36mg/mL. Many people don't like high nic at night as it affects their sleep patterns, but I seem to need it to fall asleep.
4) As far as getting started is concerned, most starter sets that come with 2 batteries and 2 atomizers will let you get a pretty good idea of what vaping is all about. The biggest weak spot in most starter kits, in my opinion, is the lack of juice. The handful of pre-filled cartridges that came with my kit barely lasted me until the second day.
Also, I am in complete agreement with JCnewbie above, the ego is fantastic. When you compare prices to other starter kits, even though it is a bit more expensive than the smaller batteries, you actually get way more battery power for your money. An eGo kit with 2 650mah batteries will give you about 5x the vaping time you would get from 2 cigarette style batteries. Which is far more convenient, and as I said above, I think convenience is the most important factor contributing to a successful switch from cigarettes to personal vaporizers.
ETA: If you do decide to go with the eGo, make sure the starter kit you buy comes with the high powered USB charger, as opposed to the standard 510 charger with adapter. My first ego kit, actually the Tornado from Totally Wicked, which is an eGo made by JoyeTech but rebranded by Totally Wicked, came with the 510 charger+adapter. The second eGo kit I ordered from HealthCabin came with the USB rapid charger, and it is amazing! Charges a 900mah battery from completely dead in just over 2 hours, as apposed to 5-6 on the 510 charger.
