When I logged in today, I had a flurry of guildies whispering me about tomorrow's maintenance.
For the record, I do not believe the patch will take place tomorrow.
Although if it does, I'll be logging into blogger and editing this statement. (joking :D)
There are two questions that are probably floating around out there, so I might as well address them now before the patch, and then copy and paste from my post into gchat/msn later :D
1) While 3.1 will most probably not drop tomorrow, 14th April, tuesday, might herald the end of season 5. I personally think blizzard will probably delay season 5 till a week after, or at the very least initiate freezes of one sort of the other. Do note that while points and rating are being reset, honor and hidden ratings will carry over.
What this means is that, you can probably expect less demand for pvp oriented enchants and gems and slot augmentations. Basically, anything that has the word resilience in it! That goes for crafted pvp gear too! If you still have those, try to limit your production of those goods. For me, I'm holding back my resilience gems and scrolls until at least one week after season 5 ends, so that when season 6 begins, a new flood of buyers will come in and snap up the augments at elevated prices.
2) My friends have been noticing that BoE epics from 3.0x have been dropping sharply in price with all the doomsayers forecasting the bombing of prices post-ulduar. While I do not doubt that prices will drop, it will not have such a rapid decrease as some people seem to think. In this confusion I've snapped up excellent deals like a surge needle ring for 70% of usual prices, I purchased it for 5500 gold and sold it around 5 minutes later for 7200 gold. The same went for a nobles deck, where I purchased all 8 cards for 4200 gold and sold it back to the market as a deck for 6000. Those are some of the items you can watch for on your server, as they are ilvl 213 epics that will still retain their value even into ulduar. If you have the money to throw, I recommend you pick them up once they hit 60-70% of their usual price, and then try to push them back into the market as fast as you can. Another good item would be arcanic tramplers or boots of impetuous ideals. Certain interesting ones would be Je'Tze Bell and Tears of Bitter anguish, but I would advise greater caution when dealing with those.