The huge ask wall on BFX offered whale shorters (and non whale shorters) a way to close their positions with no slippage. That basically means that they were able to buy a lot of BTC at fixed price and without raising the price in the process.

It is altogether very bullish because:
- The ask wall was of the manipulative kind (as far as I can tell)
- Shorters no longer believe they will get new/better opportunities for closing their shorts at a lower price
- They are now focused on accumulating BTC (and when done with that raising the price)

I agree with Davyd05 that all these unclosed shorts could have provided the fuel for a very bullish scenario. Also the shorters might still be able to keep the price down while they accumulate although I doubt it will go much lower from this point on... There are still shorts that needs to be closed and coins that needs to be accumulated (Edit: added buy pressure as Teppino pointed out). I believe we will go sideways or up from now on. That is what I am hoping for anyway  

Everybody pack your wallets and cut your foot looses!