Two comments: Licensing & Distribution
 

Licensing

Why not just use a GPL or MIT license. I appreciate this license is simple but you are opening yourself up to all kinds of problems by trying to write your own. GPL and MIT licenses are established open source licenses that are designed to protect authors/contributors. Use an industry standard instead of trying to reinvent the wheel at every opportunity.

Distribution

I'd prefer hosting on github and using git as the version control system.

I second this as with Git we'd be able to easily fork the project to do our own extensions which can be easily pushed back to the master.
Maybe you should consider this.

At first glance, I thought the license clearly violated the OSI definition of open-source software. On closer inspection, I find that it does actually seem to meet it, if you read it properly. This part gave me trouble:
But it seems like this means that you can sell derivative works, but you then have to make their source code available for free to your customers. This requirement is then parallel to the OSD's stipulation
But a lot of the license seems unclear to me. A FAQ would be nice:

• Can we fork it? (Assuming we indefinitely distribute it as a pristine unmodified copy plus patches.)
• Can we sell modifications? (vB tolerates that even for vBulletin itself, so I assume yes.)
• Are we allowed to not release our changes freely, if we don't distribute them? We have to provide a copy to vBulletin (point 5c), but do we have to let vBulletin redistribute those copies?
• Are we allowed to release our changes under the LGPL, say, or some other license incompatible with the vBOSL? This would mean vBulletin couldn't easily incorporate them into the next version, which seems to negate the point of the copyleft provisions.
• What does "application programs, reusable components and other software items that build upon or enhance the original or modified versions of the Software" mean? Does this mean "derivative works"?

The major advantage of using an established license is that people usually have a clear understanding of what exactly it means. If you really don't want the same functionality as any existing license, could you at least phrase it as a diff to an established license? Like the suggestions here. E.g., release it under the LGPLv3 or later, except with additional requirements like "You must provide any modified versions to vBulletin upon request even if you didn't distribute them", or whatever.


Overall, though, this is promising. When I switch to 4.0, I'll very likely use both of these, and will certainly contribute back any improvements I make. I'd have preferred git too, but it's not hard to change later.

I have read the Licensing and point 5c can maybe work in the US but i doubt it will hold ground here in Europe. Even 3b could be a problem here in Europe because when i write a code i am the copyright holder of that piece of code i have written also you state that code under that license if i make a new license for the stuff i write and exclude vbulletin or other staff members to use that code you are bound to that.

IB made a Licensing model but they should have adapted a current model to suite there needs. This model is incomplete and to simple solution is to use a existing one that you can adapt.

Yep, this is exactly what I was getting at.

I don't work on open source projects unless they use an established license without extra conditions. This makes it simpler for everyone as we already know how the license can be challenged and how it can protect author works.

With regards to licensing, apparently releasing this as you said would be impossible since apparently, the vBulletin software itself would need to become a part of that license, - not sure how though.

Thats not entirely true Project Tools is something that runs on vBulletin, if i made a modification and released it under LGPL it would not mean that vBulletin will become LGPL. But why not put the Project Tools under CC, make a foundation for all project that you are willing to release under CC that way the foundation is the holder of that work and vBulletin is protected. Don't know what the startup costs would be for a foundation but here where i live its around 300 to 600 euro, after the foundation is made you grant the rights to the foundation of the software and there use noted in a legal document after that they make it public under CC.