Dwolla Instant is a non-issue. They have already been overwhelmed and had to cut the service off. Another amateur move by dwolla, but did anyone see giving away free money as going well?
Regarding the slump...what slump? Bitcoin is double the price of last month.
They just limited the number of users at first. Wise move when you are extending credit if you ask me. Also, probably required by whoever is extending Dwolla the credit to back this feature. However, 2 days ago I clicked the 'notify me when available' button and now I'm eligible. 2 days is a pretty reasonable wait time. So yes, the Dwolla instant effect may not eliminate the weekend/holiday slump effect, it will lessen it as I said. As it becomes more available it will probably come close to eliminating slumps due to no USD funds available.