Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Some things are better, some got worse, and some became bad. Overall, I'll keep it because of copy/paste, MMS (soon), and built-in tethering ability.
 
My iPhone 3G runs great on 3.0 software. It is very speedy and even after I jailbroke 3.0 it was pretty snappy. The only place I really experience lag on the 3.0 software is the transition from landscape to vertical in SMS. Sometimes it just won't switch and other times it just takes really long to switch modes. Aside from that, I find 3.0 to be much, much better than 2.2.1.
 
This is very interesting, all these 2G and 3G users claiming that 3.0 performs worse for them than 2.2.1 did.

I am exactly the opposite. I loved 2.2.1, and was afraid that 3.0 was going to add back a bunch of bloat again and slow down my phone. After all the many disappointments that had been handed to us, 2.2.1 was a breath of fresh air. Safari FINALLY felt stable, and that OS was a steady workhorse for me for 6 months.

3.0 is FASTER on my 3G, and this is on a jailbroken device, too. I was extremely pleased with the performance of 2.2.1, but 3.0 is snappier in all respects. Furthermore, it is quite obvious that Apple put the OS on a RAM diet (which it severely needed). The other day I was browsing around with Safari while also listening to Pandora and signed into Nimbuzz (thanks to Backgrounder), which is a feat that I NEVER dared try with 2.x of any variety...Safari would cause the backgrounder applications to crash out in no time. And I regularly see 42MB+ of free RAM on bootup, which I never got close to with 2.2.1.

There is only one area of 3.0 on the 3G where I can honestly say I notice lag that is somewhat annoying: when CLOSING, not opening, apps. Sometimes it's fine, but I would say that 1 out of 2 times the app will not close out immediately when I press the home button. Somewhat annoying, but liveable. I have a friend who also has a 3G running 3.0 and has the same issue, so I just figured that it was a common 3.0 glitch that has probably been fixed on 3.1 already.

Anyway, that's my $0.02. Oh, and BTW, I just typed out this whole post on my iPhone! (would never dare try that with 2.0/1/2; Safari would have crashed by now)
 
Yes but I can't stand using the 3GS right now because I hate the screen and build quality. I'm going to try to return it tomorrow. Wish me luck!

This really made me laugh. Seek professional help for your your own sake.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.