Technically speaking they're not saying there won't be boxes on the shelves, only that there won't be at launch. And let's agree that not having boxes on shelves is not the same as not doing marketing.
I think a low profile launch is a really prudent move.
Remember the expansion when Haven was introduced? (Can't recall which one that was). That one was pretty high profile and advertised. I took a blue guy to go see Haven, and there was all these newbies standing around in a field, being unable to move because some stack of hay or such got stuck in their backpack and weighed 3000 stones.. Now let's not have any of those incidents again please?!?
Those of us that are still around have really high fault tolerance for UO expansions and patches, otherwise we would have been long gone. Heck, most veterans are pleasantly surprised if an expansion will even install on first launch
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Let SA come out quietly, hopefully in a while the most obvious bugs and glitches can be fixed, some will reactivate and the shards might get semi-populated for a while. Then go advertise and try to get new players into a working game.
If you go bragging about legacy and having been around for 11 years, you better make sure you don't go advertise a faulty product, or it's going to backfire big-time. I can already see the reviews.. "UO's been running for 11 years and it still doesn't work!".
The future of UO rests completely on SA's shoulders. If it delivers, then fine! Let's think about getting more subscribers. If it doesn't deliver, at least let UO fade away with some dignity left, without having to suffer the blow of a high profile launch that backfires and makes everyone conceive the game as a shoddy, old, bug-ridden artifact that still hasn't got it right after 11 years.