is it true somone can DOS a vb site?
 

is it true?

Anyone can DOS any site,

Denial of Service. An electronic attack whose purpose is to prohibit an opponent the use of a program or an entire system

If they nail the server just right they can take it down. ;)

But most hosts are getting caught up on that so it isn't quite as common as it used to be.

Yes, it can. It does actually happen quite often, castlecops is a site that is under attack a lot of the time. That's why they now have a dedicated forum for DOS :)

I didn't say it doesn't still happen, I said it doesn't happen like it used to as there are better firewall routers, among other things, to clock it now. Castlecops is a whole nother story, too, by the way.

Agreed, Castlecops is a special case.

Read up at grc.com about DRDOS attacks, crazy stuff (bit old though).

Any site can be DDoS'd really....

And alot of it depends on who you PO and/or if you are offering security programs on the site. They'll do it just to prove a point.

is there a way to avoid it?

Well, tighten security is the only way. But there is an exploit in everything, it cannot be stopped.

Going a little off topic, but software developers (example vBulletin) can only patch security issues until another exploit is found. The bad guys always find the exploits first...