Is that for billing address or rate centers?
Wondering how that compares to HostGator? (demographically)
If 99% of HostGator is in one place, then your VOIPo inventory might be in high demand there.

You should also consider a discount perhaps, for those who have a HostGator account? That might make people consider both -- like multi-car insurance discounts.

I don't know if it can mirror the HostGator sign-up terms (likely tricky), so that you get a year of discounted VOIPo for a year of discounted HostGator. Just considering ways that lock in the loyalty ...

Maybe a special discount page signing up for both at the same time ...

I know . . . that would get too convoluted to scale as a promotion.