skivaly21:We are in debate between having "SharePoint as Service"
Opening a free demo account and trying it yourself or simply just googling requires less time than debating.
skivaly21:will I be able to open InfoPath Designer on my laptop and publish an InfoPath form directly to a Form Library, make a data connection or create a new content type from a InfoPath form?
Yes, I use Office 365 (Sharepoint 2010 Online) site and publish all kind of Infopath form templates to Office 365 site, create data connections, etc.
Though, there are some restrictions and limitations. I cannot say that they are very well documented.
Besides, server side of Sharepoint Online is being continuously patched, updated and upgraded by Microsoft.
Opening Infopath Designer on your laptop does not depend on anything, you can do it even without network connection, work offline and then publish or submit your changes to Sharepoint when online. It is possible to use Infopath even without any Sharepoint.
skivaly21:some say I will have to package all the InfoPath files into a WSP and upload it through site settings
I use Infopath Designer 2010 to create and publish Infopath form templates to Sharepoint Online site from x86 (32-bit) Windows XP Pro in which I cannot even install Sharepoint or package/create Sharepoint projects in Visual Studio (I have 2005, 2008, 2010)
skivaly21:would I be able to use custom code if needed?
Yes. You will need to install VSTA (Visual Studio Tools for Applications) as part of MS Office setup (you can add components later if you did not install it from the start).