Will hosting multiple sites one one ip, decrease PR? Heard from hostagator that it will. Any other opinions on this?
No, that's completely false. However, if you are planning to link all these sites together to build a network, then those links will be devalued and may be penalized, so don't do that.
Thats what I thought. But some people believe that theres notthign wrong with linking within the same ip. Very debatable i'd say.
Well, there's nothing wrong with linking between these sites, if it makes sense to do so, just don't over-do it by linking between them on every single page.