Alright, lets let a techie dude explain whats going on here :)
NG is now powered by CSS. CSS (which stands for Cascading Style Sheets) is basically a way of seperating the fancy stuff on a site from the text/links and boring stuff.
Anyways, unlike the old NG (which was just plain old HTML and Flash), CSS pages get saved onto your hard drive in the cache so it just gets reloaded on your computer whenever you visit a page, making the site A LOT faster after loading it just a few times.
Unfortunately, its not too good for things like forums, because everytime you type a letter the template is reloaded, causing lag on bad comps (like mine, I now have to type my posts in Notepad and then copy & paste it onto my post or else I'll be waiting around for ages to make sure I didn't make a typo XD).
So as you can probably make out, CSS has its ups and its downs. So far, I've seen more ups than downs here, but the major down (POST/REVIEW LAG OMGGGS!) is killing NG.
Also, Flash Portal is broked now :(