First of all, even if it's not Choiced, Staraptor is played like a Choiced Pokemon. What I mean by this is that it is reliant on prediction to get KOs.
For example, Max Atk Adamant Life Orb Staraptor deals 18.64% - 22.03% to Relaxed 252 HP/0 Def Steelix with Brave Bird. Close Combat deals 49.72% - 58.76% to the same Steelix.
120 Atk Stone Edge vs min/min (-1) Staraptor: 93.25% - 109.97%.
So if Staraptor Brave Birds on the switch and Close Combats, it's not going to kill Steelix before it itself dies. However, a Close Combat on the switch will 2HKO.
If Slowbro switches in on Staraptor's Brave Bird, it gets killed the next turn. However, if it switches in a Close Combat, it will survive the ensuing Brave Bird and be able to defeat Staraptor through paralyzing with Thunder Wave.
These would not really be "counters" by the definition because they are 2HKOed by Staraptor.
But look at Salamence in OU. Draco Meteor/Fire Blast/Outrage/Earthquake @ Life Orb can hit 2HKO just about everything except for a few Pokemon. (Cresselia and Bronzong come to mind.) But it is reliant on extremely accurate prediction in order to do so.
This is comparable to Staraptor. It must hit Steelix on the switch with the right move (Close Combat) to defeat it. There are other examples, including Spiritomb, Regirock, Registeel (depending on its EV spread; the standard one posted in the analysis can't really do this), Rotom (actually Rotom isn't 2HKOed by LO Brave Bird), etc.
To sum my point up: Staraptor does not have many "counters" by the book definition. Its sweeps, however, are capable of being hindered if the user of Staraptor does not use the correct move. There are both Pokemon that can switch in on its STABs and not get KOed by an ensuing hit, and Pokemon that can switch on Close Combat and not get KOed by an ensuing hit.
I'm not sure if I can use this as a basis for this argument, but I do recall reading one similar to it in a discussion about Salamence. 
Now, if Staraptor is Choice Banded, it's even more reliant on prediction. If Nidoqueen switches in on Close Combat, Staraptor is forced to switch. I think this was discussed in the old UU thread pertaining to Aerodactyl.
If these points have already been stricken down, I would like to see the thread where it was. edit: Actually I would appreciate just seeing it if anybody recalls where it was posted.
 
	
	
		
		
			Crobat is MUCH, MUCH, more useful than that.  How much does a Cross Poison do.  Renember, it also has a high crit rate and a chace for poison.  Use Max Attack.  Also, Roost negetgates the Electric weakness meaning Crobat CAN and WILL stall Luxray out.  If it stalled my Porygon-2, it is going to have no problem stalling Luxray.
		
		
	 
Who runs Cross Poison? It's not even on the list of most used attacks by Crobat according to Doug's stats. Cross Poison has a chance of Poison, but Thunderbolt has a chance for paralysis, not to mention that Luxray can just run Thunderwave anyway, forcing Crobat into a guessing game between Taunt and Roost.
For the record: Max Atk Adamant (most run Jolly mind you) -1 atk (for Intimidate) Cross Poison on max/max Luxray: 15.11% - 18.13%. In fact, if you crit three times it's a 4HKO. 
Thunderbolt on 104 HP/0 Sdef Crobat from min atk Luxray: 35.01% - 41.84%