VB5 was out for a long time btw, it was alpha before beta, staff also advertised alpha testers so no they didnt just their gun, VB5 had been n development for some time

I'm not talking about the beta. I know about beta releases but I am expected to take advantage of a discount and yet nobody can tell me what the benefits are of it.

It seems a straight forward question. Not the benefits of the Beta but the benefits of VB5 as a product. Like someone at Apple can tell me why iPhone 5 is better than iPhone4.

Obviously the product has improved hence a new version but improved how?

What changes have been made that benefit me as a site owner in the current social media world and benefits the users?

the difference between different vbulletin versions 3,4,5 are that whenever you upgrade the vbulletin, You get
1. More server load
2. Slower page Loads
3. Loses Search Engine Rankings each time you upgrade (vbulletin 3 has index.php as default page, vb4 has forum.php/content.php/activity.php as default pages, while vbulletin 5 make a mess for search engines by moving all pages to core directory and change the whole sitemap) And search engines needs to re-index all your pages again after upgrading to vb5. i have read about the two layers system for more security in vb5,i have a simple question that it is good for Search engine rankings to change the site structure so rapidly?
4. You get more new bugs after upgrading.
5. Every time vbulletin upgrades its script the coders have to learn code again from the scratch to make new mods or port old mods to run with new script.
So whats the benefit of buying a vb5. If there is any? please mention thanks,if there are some solid reasons behind the vb5 then i will have no hesitation in purchasing a vb5 license.And one more thing i have noticed that we can't customize the design and templates as we used to do in vb4. is that true?

We can.

can we add customize header easily to make the vb5 to look as the part of our site? that is what we can do easily in vb4, and i also noticed that there are so much less style vars in the styles of vb5.

You appear to be misinformed on some of your statements.

3. The URLs will never have /core/ in them and all your old URLs will redirect correctly to the new URLs if you install vBulletin 5 in the same directory VB4 was installed in.

5. The upgrade from VB 3 to 3.5 added a hooks system so yes it was a new way of coding mods but the template syntax was the same. The upgrade from 3.x to 4.x had new template syntax but the back end (hooks) code was exactly the same as VB 3.x. In fact the majority of my mods work fine on 3.x or 4.x. The upgrade from 4.x to 5.x has removed the hooks system in favor of file extensions, so yes it is another big change, but the template syntax from 4.x works in 5.x, so that is something. There hasn't really be a release where everything changes.

1 & 2 - Remains to be seen when it is out of Beta
4 - This is true, but honestly expected- going to a new major version will always bring new bugs.

Thanks for your detailed answer, hopefully i will give a try to vbulletin 5 when vbulletin 5 connect stable version will release. Just one more question please, i am thinking to purchase a vbulltetin 5 connect and will integrate it with my custom build php site, can i integrate vbulletin 5 seamlessly with site design? i am worried about vbulletin 5 header with site builder, that will create lot of problems for me when customizing it.

vBulletin 5 is not designed to integrate with other software. Your ability to do so will depend on your ability to custom style both vBulletin and the other software to make it look like they belong together.

will there be a vbulletin 4.3? or will vb4 not upgraded anymore?

I have just installed VB5. Apart from the fact it took me about 12 hours to figure out a .htaccess conflict I will be using it on a fledgling live site. This is my first VB forum and to be honest I dont want to learn how to use 4 and then have to use 5.

I also like the responsiveness of it out of the box.... Not sure if there are responsive themes for 4, but anyway I will report back in a couple of weeks!