Flash or HTML? A scratchy question which is being asked since prehistoric ages.

I thought about this too much, especially last few years. Is Flash correct thing to make a website? I've calculated advantages and drawbacks one thousand times. I say last few years because, SEO, blogs, social networking madness are regular parts of our lives. I say last few years because, I used to make Full Flash sites usally. You can think that I hate Flash while reading lines below but I can say boldly I'm an advanced Flash, Flex and ActionScript 3.0 developer. Yes I love Flash but I thought honestly. Actually these are not equivalent technologies bu our goal is to make a website. In short our question is; What is the best technology to make a website? Of course I exclude some technologies such as Java and Shockwave :) Only Flash and HTML/PHP/CSS/JavaScript and maybe MySQL. I'll call second group as HTML shortly to make a goodness to my fingers and keyboard :) ...and there is a third competitor, it's AJAX.

FlashCookie7 lets you store small cookie-like data on user's computer. When your website/application needs, you can retrieve previously stored data from user's computer easily. FlashCookie7 is a wrapper class for Flash SharedObject class. But FlashCookie7 has a simpler implementation and usage.

FlashPlayer has an isolated sandbox model to provide personal information and data security and to prevent theft.

When you compile (or export) a swf, you must choose a sandbox model which are local only and network only. For example a swf compiled for local sandbox can not retrieve data from internet, can not load any type of file such as xml, jpeg, png, swf and can not send data via GET and POST. Also, a swf which is compiled for network sandbox can not access any local resources (except SharedObjects which is a minimal, isolated data storage system like HTTP cookies).

To bypass this restriction, i mean to make a swf to access any local or remote resource, you can change FlashPlayer settings via FlashPlayer gui but this is a bit complicated and an end user might not set it correctly and might be a bit painful.