Although I don't disagree with this, it still wouldn't solve one of the main problems with the current Opera browser: The too-old flash support. We're still dependent on commercial licensing of Flash for N800 from Adobe.
Most of the time I find Opera a quite nice browser, with its switchable 'optimized view' mode etc. Other than flash I only know about a couple of issues:
o Not working for some types of Ajax sites, e.g. Google docs. Not critical for me. Possibly this could be solved by switching to another browser.
o Missing support for java applets. This is critical for me, and not something I can work around (banks). Nokia doesn't seem to want java applet support for some reason, or thinks it very low priority. But still, if the browser was open it could presumably be added by third parties. Maybe.