Sure, Opera Mini may (or may not) already be the most popular mobile browser in the world — but why stop there? Following up on the Android release of Opera Mobile 4 just over a year ago, Opera has just launched Opera Mini 5 for Android into public beta.

The jump from version 4 to version 5 is pretty huge, introducing a handful of features that Opera says “makes your mobile browsing experience as close as it can be to your desktop experience.”

The biggest change here is probably the introduction of tabbed browsing — a must, given that just about every default smartphone browser supports it out of the box at this point.

Some of the other big new features:

    * Speed Dial: Gives you one-touch access to 9 of your favorite sites.
    * Password Manager
    * Opera Link: Syncs your bookmarks (and Speed Dial) between your handset and your desktop (be it that you’re running Opera on your desktop, that is)

Is Opera Mini 5 a worthy contender to the default Android browser? I’d say so. Opera Mini’s primary selling point is that they pipe everything through a data compression proxy before sending it to your handset. For those days when 3G just isn’t as fast as it should be, it’ll save you time; for those of us not on unlimited data plans, it’ll save some money. Alas, the current Beta doesn’t support multi-touch, which may very well be a deal-killer for some

Still: throw in Opera Mini 5’s seemingly rock solid build quality and its pretty dang decent UI, and I’d say it’s worth giving it a serious test session at the very least. Look for it in the Android App Market.