I'm interested in hearing what other WP.com users think about the default mobile theme, and mobile browsing in general, including issues related to fixed-width vs. flexible width themes.
(Note: I do not currently pay for the CSS upgrade, altough I'm starting to give it serious consideration. It's very reasonably priced, IMO, so cost isn't the issue.)
I've never really liked the mobile theme, because it strips too much of my blog's visual identity. The customizing I do with the theme's default options are important to me, and to lose so many style elements - things like background color and the customized sidebar and footer - bothers me.
So, then I thought, the iPhone has touchscreen gestures (double tapping and pinching and zooming) that make it incredibly easy to isolate the main content columns on websites, I only have a two-column blog, so I might as well just disable the mobile theme. This way the whole blog loads initially, which might take a little longer, but then at least my whole visual identity is intact, and then the reader can zoom however they see fit.
Problem is, when I came to this conclusion, I was using Twenty-Eleven, the best all-around theme I'd tried in years, and because it's a flexible-width theme, it gets messed up in a mobile browser. (My custom header image - which in my case, at the time, contained the title of my blog - was covered over by the search bar, the background color was not visible at all, and the sidebar was bumped down to the bottom, beneath my last post, where it looked terrible.)
After much playing around, I settled on Bueno, a fixed-width theme, the mobile theme is disabled, but there are a few things about Bueno that I don't care for (one example: I don't like that only the day and month is displayed with each post...when someone views an older post from a previous year, the only way they can tell what year it's from is if they look in the URL).
Anyway, I find it an interesting little dilemma, and I'd be curious what others think about it, what others have decided they'd do about these issues, etc.