Jump on the Note 2, they are in stores waiting to be bought. Another great thing about the Note 2 is since its been out for a few months you can get it at walmart for a very good price. I would not get the S4, once you go Note you can't go back. The Note 2 is a great phone and is as future proof as you can get. The Note 3 wont be coming until the end of the year. There is no reason at all for you to wait for the S4, in fact even if it where here, I would still go with the Note 2 and I know allot of other people that would do the same.
Just go check one out, look at beautiful display. The awesome camera features, the S-Pen can do some amazing things. It also makes photo editing using Photo Shop Touch almost as good as what I can do on my desktop. There is just so much features built into the Note 2 there are way to much to list. Did I mention the Display? Its just one of the best things about the Note 2, Super AMOLED HD PLUS display. I say PLUS because it uses RGB color matrix. So even though its 720p you get much better color, contrast and 2x the sub pixels compared to the S4. It's much better then the display technology used in the S3 and S4 they are using pentile, rather then RGB.
Once you go 5.5" you will never want to go a hair under. You also get used to the size very fast. I hold my friends S3's and S2's while they are playing with my Note 2 and WoW, the S3 feels smaller but the S2 its just tiny..
The fact is unless you hold your phone about 4-5 inches from your eyes you wont notice the difference from 1080p to 720p on a display under 7" and like we went over, the S4 uses a pentile display anyway so it makes getting the Note 2 a no brain'er
But if you just can't make up your mind and are willing to wait until the end of the year then the Note 3 it is. But if you want the best of the best, go pick up a Note 2. You wont be sorry, you can hold me to it.