How does my wrt54g v. 3 router compare to newer options?

My router works fine trying to figure out if I should update my router or not it is a link sys WRT54G version 3 router with DDWRT firmware installed. 

I was thinking of either upgrading to the  ASUS RTN65U router or a Link sys E3200 router. I bought an E2500 router but learned it is way below par of the 3200 so I was going to take it back. How much better performance will I have if I get a dual band router 2.4 ghz and 5 Ghz band as well how important is the gigabtyte ports? How much more of an improvement would I notice with a newer router. 

I have several laptops, droid phones that use wi fi, several 360's computer and PS3. I also use a lot of online gaming and movie streaming.