You have HN's use of tables to thank for this one.
No. Mobile Safari is not a very good mobile browser.
If Mobile Safari is a bad mobile browser, what qualifies as a good one?
The non-WebKit version of Opera Mobile and the Android version of Chrome are both significantly better IMO.
I'm using Opera Mobile on Android 2.3 and it reflows text nicely. It has some other problems, but it's far better than the stock browser!
I've been using Firefox Mobile on Android with great success.
Mobile Safari only reflows the text in Reader mode. But reader only works on a few select websites. Sites like slashdot and HN aren't supported and force you to horizontally scroll when the text is zoomed to a comfortable level.
I'm not sure what I hate more, horizontal scrolling or not being able to zoom.