Blizzard has announced time and again that it has no plans at all to create a single player, offline version or patch. Apparently it would require an enormous amount of work and basically entail rewriting mass portions of the game's code. I highly doubt they'll do it, in any case. As pointed out, I've read that the real reason (beyond DRM, even) for the on-line always requirement is that Blizzard figures a much higher percentage of players will use the cash-for-loot auction house this way, thus providing Blizzard (who takes a cut) with a constant revenue stream from gamers, almost as if it was running an MMO (albeit a cheap one). Of course, this will probably be used in part to cover server costs, but Blizzard wouldn't have made this move and risked alienating fans if it wasn't going to make the company a boatload more money.
I've decided to skip D3 for the time being, possibly forever (pending a stable, reliable, off-line option, either official or otherwise). It really, really pains me to say that; D1 was one of the very first games I played on my own and I have extremely nostalgic memories of staying up way past my bedtime (I was 8 I think, maybe 9) and being terrified (because that game was damn atmospheric and scary) and playing for hours on end. Ditto D2. And I realize that pretty much no one who worked on those games worked on D3, but still. As I mentioned in an earlier post, I always played single player. That's just how I roll. I don't want to deal with all the potential headaches (and other players) that online play necessitates. In other words: Blizzard, you lost me, one of the most loyal Diablo fans out there, thanks to this godawful and greedy decision.
Looks like it's back to D2, Torchlight, Dungeon Siege, and Arcanum (plus maybe a new game of Icewind Dale...). I guess I can't complain about that.