Sony or Canon or Nikon?

Don't buy Sony. It doesn't support WiFi.

Canon and Nikon have wifi DSLRs.

Each of these is a quality camera. It is just personal preference, so go to a camera shop and handle each one. One of them will fit your hands the best.

First off, pros are NOT going to mirrorless cameras ! Only someone selling EVIL cameras would tell you that ! A mirrorless camera is no more than an advanced point & shoot camera that has a lens that you can change !
I'd go with the Nikon myself. But any D-SLR will be better than a mirrorless camera.
I know two pro photographers, and both of them wouldn't touch the NEX system.

Dont go any of these.. Buy a mirrorless camera that can get same features and picture quality like GX1, One from NEX that suits your budget..future is not DSLR.. even photographers and pros switching from DLSRs to compact interchangeable lens systems

http://mirrorlessforums.com/

Consider Nikon D3200 some features about this camera:
1. Pictures are amazingly crisp and true to the color, simply beautiful
2. FPS is fast and satisfying
3. Takes Amazing videos with great sound
4. Love the view finder, specially, since in this camera it's smarter and more detailed/informative than most LCDs

I would get the brand that most of my friends have. So that you can borrow lenses and accessories from them. I would gladly lend you my Nikon gear if you're staying at my neck of the woods.

You can't go wrong with any of these... Personally I'd go Nikon, not cos it's better, I just 'like' it more.

Canon and Nikon are much more popular, and it's because they've been in the DSLR game for a longer time. I'd also recommend you to look at the Nikon D5200, it blows all 3 mentioned models out of the water!

Here's a 700D vs Nikon D5200 Comparison - http://www.the-dslr-photographer.com/canon-rebel-t5i-vs-nikon-d5200/

Any of them, but look at the Pentax K-500 as well - it has a 100% viewfinder and meters with manual focus lenses (the Nikon won't meter, and the Canon and Sony won't even take them).

Find a dealer and look at all of them, then just choose the one that feels right in your hands. You're the one who's going to be spending the time and effort learning to use it properly.

Oh, and if you expect that the act of owning a DSLR will make you a photographer, you'll be sorely disappointed, whichever you get.

Too bad Pentax does not have entry-level!

In this case, any. They are all the same. All dSLR's are basically the same. All are good, all brands and all models. That is if you take the Sony out. That's an SLT, not dSLR.

I think the Canon 700D is at the top end of the entry level group.
Sony A58 is actually an upgrade to the A37... they discontinued the A5* line so the LCD is smaller and only half the res of the A57. The A58 makes up for that by having a larger 2.4mp OLED viewfinder meaning if you have good eyes you need never take your eye away to check the shot. Sony's A65 is nearer to matching that Canon.
The Nikon D3200 doesn't have an articulating LCD, you need the D5200 to get that.

A consideration should be if family or friends have the same brand because then you could share lenses and accessories.

Even contributors learn from other contributors. I was unaware that Pentax has a new entry level K500 camera. I would buy the Pentax K500 in the kit with the 50-200mm lens included. When I re-entered the world of DSLR's after having come from 2 1/4 film cameras. I choose the Pentax line. First because I was/am most comfortable holding the camera, locating controls, but most important the viewfinder was the most comfortable for me. After I purchased my Pentax DSLR (the model Kx at that time-now discontinued) I found the viewfinder eye piece would adjust to my strong Rx of y glasses. As a result, I just slide my glasses up on my head so I can seen the entire frame in the camera-a real pleasure for me as I construct my pictures in the viewfinder!
If the three cameras, are "cemented" in your determination, I would definitely delete Sony!

Good Luck!