Seperate IP's for each domain?

[MMemmer]

From the way that it was recently explained to me unless each of your IP's is on a seperate Class C it will make absolutely no difference to either your submissions or your rankings. Four or five years ago when these the IP's were not tracked/monitored like they are today it did have an impact, but now because of the ARIN guidelines to cut down on SPAM and other irregular activities, the value of having individual IP's has been reduced to ZERO.
It would also be a technical nightmare to try and implement this type of an IP structure on a fully routed network.
You should not have any problem in using a single IP for the entire 100 domains that you have mentioned.
Finally in closing yes I would like the opportunity to discuss your hosting but I should also state that from I know of Jupiter that they are also a quality host.
Good luck.