Sasu fans getting ahead of themselves
You Sasuke fanboys are getting ahead of yourselves. Too many are already saying in all seriousness that Sasuke is better than Itachi. Now you may like him as a character more than Itachi, (which I wouldn't understand that either) but c'mon let's take a closer look at the relationship and comparisons of Itachi and Sasu.
Anyone who is familiar with me on here knows I don't comment often and I dont' like to post long comments or threads but I very rarely state something that doesn't correspond with the manga and/or show. so you'll have to fact check anything I say yourself and prove me wrong. So here it goes.
1. Itachi took down Deidara with ease upon meeting him. Sasuke had a much harder time with him. Now I know the first thing you will say is that Deidara trained himself to defend himself from genjutstu. Well compare Sasuke's genjustsu at the time to Itachi's. Honestly Sasuke still can't f**k with Itachi when it comes to genjutsu when Itachi's at full health leading to my next point.
2. Sasu vs Itachi was not a good fight to compare the two brothers' strength at least not in favor of Sasuke. If anything you'll see that Itachi would've and could've won the fight easily at full health if that were his intention. Now in all honesty Itachi DID win the fight, despite his illness for those who were paying attention. Despite all of Sasuke's efforts Itachi still had chakra left with Sosanoo in tow. The time Itachi spent transfering the last of his power to Sasuke could've been used to strike him with Totsuka or even to actual rip his eyes out. but we see that wasn't his intention.
3. Itachi and Sasuke vs. Kabuto
Now although Sasuke was of great assistance to Itachi in this battle we see numerous times where Itachi has to save Sasuke's ass. Babysitting him and protecting him as usual. And at times becomes a hinderence to Itachi. This proves Sasuke still has a way to go in catching up to Itachi.
When it comes to Taijutsu and raw strength, and control of Chakra nature I'll give the torch to Sasuke. However when it comes to intellect which in the shinobi world we see takes precedence over most other attributes, genjutsu, and in weaponry (Itachi's Yata and Totsuka) Sasuke doesn't yet measure up.
EDIT: To make it clear now, my main points are that I don't believe Sasuke is a better Shinobi THAN Itachi YET. And that in the event that Itachi didn't care whether Sasuke lived or died in a serious fight and in prime health, 7 times out of 10 Itachi would come out on top.