I just downloaded it and tested that, it's not present, zooming is now as bad as in other android browsers (but some of the HN comments are in bigger size than others so there is no need to zoom, it's quite a strange behavior though)
Also as another user pointed it, tabs on the top is not practical and unreachable (especially on big devices like samsung GS3)
How about the "scrolling guides" when you're zoomed? Not sure if there's a proper name for that, but with Opera when I zoomed and the text reflowed, it would lock me to vertical scrolling only as long as I don't wiggle too far horizontally. Easily my favourite thing about it.
Here's the trick for me, using a Galaxy S2, with Android 4.1.2 (JB, but it worked with ICS)
It works with Dolphin and the Stock browser.
1-Open the stock browser
2-Go to Settings->Advanced
3-Check Auto-fit pages
Now, using the stock browser or Dolphin, you can zoom in a page and then, if you double-tap the page, the browser will reflow the text to adjust to the new size.
Note that if you double tap again, it will zoom out. So, to reflow, first adjust the zoom, then double-tap.
For what it's worth, the latest Firefox for Android has an option in Preferences called "Reflow text on zoom". It may be what you look for (but I don't use Opera enough to be sure).
Also as another user pointed it, tabs on the top is not practical and unreachable (especially on big devices like samsung GS3)