Yeah, I know you're all sick of "the sky is falling, btc will be 5$, everybody run..." type of topics and I'm really not trying to make another pointless dicusion about btc.
[TL;DR] short introduction of myself, you may skip this part
I started mining using a single 5850 (now running at 360 Mh/s) 20 days ago... I've constantly sold my bitcoins on mtgox... I've sold my first bitcoins for 9.50 (I thougt it will never go higher than that) but I've also sold at 29$.
When the "sky fell" from 30 to 10.25 I was waiting with buy orders at 10.1 and below... I misscalculated with 0.15 btc (damn it).
My last salles where at 19.50 because I thougt the media coverage surounding allinvain's 25.000 btc hack will take the price down... alowing me to buy some underpriced btc. Of course I've never expected the "holly shit" moment that happened this weekend. I'm not so woried though... most of my money in my mtgox account was USD (prepared to buy btc... actually right before mtgox was taken down I saw that my buy orders placed last weekend (from 10.1 to 7.1) we're fullfilled... but I supose they're gonna be rolled back by mtgox).
Now I have to admit that I never understood what exactly made the price go up from about 6-7$ (that's when I started mining)... Sure, dificulty increase is an explanation... but I guess it's only one of 3 major factors that made the price rise to 30$.
1. Silkroad: drugs, guns & stuff - I think this is the "real" value behind btc. A curency is only as valuable as the things you can ONLY buy with that specific curency. EURO has a certain value partly because in order to buy a german car you must pay for it with euro (even if you pay usd to your car dealership, eventually they will convert it to euro). Since the only way to buy weed online was trough bitcoins ... well, you get the picture... You could actually see a huge increase of btc value a few days after Gawker (lifehacker, gizmodo, etc) published an article about silkroad.
2. Speculators - Now btc is volatile... and volatilty is good for speculators... With prices going up and down with up to 10$/day on a regular basis you don't even need leverage to make a good profit.
3. Investors - now they maybe called hoarders, enthusiasts, but basically these people were investing in bitcoins, they were buying bitcoins and they were keeping them, they are similar to speculators but they are (or were) more interested in the long run.
Unfortunately I think the "real" value of btc was quite small... and most of it's value (and the cause why price went balistic) was due to speculators and investors. The question is, how many of these people have lost faith in btc after the recent mtgox fiasco... Some speculators might not be scared away since this might be an oportunity for them (a constantly rising value of btc is not good for speculators) but some might be scared away. Investors will most likely be scared away unless they are true btc fanatics. Drug adicts will certanly not be scared away, since the value of weed for them is constant... and silkroad prices are adjusted acordingly... they do not really care if 1 btc is 0.1 usd or 100 usd... though I guess they like to see stability and maybe slight increase in value... but they don't really have a choice to move to another curency.
I believe that once mtgox will be back we will see a drop in the demand for btc (and price will follow naturaly) untill the real demand (and price) will be reached and prices will probably become stable around that value. The question is what will the price be: 5$, 10$, 15$ ?
My guess is between 10$ and 15$.