Hear me out on this - working up a plan for my house.
Although no where near the amount of consoles as you have, i have the 3 current (ps3, wii and 360) - tack on an apple tv2, dvr and PC (for various movie reasons) and the fireplace mantal is getting a bit crowded- it spans the width of the room; brick fireplace in the middle flanked by a built in bookshelf on each side.
so i'm gonna gut the entire thing; granite over the fireplace - leave the tv in place on top of the mantal and on the left hand side will go a 19 inch network rack.
4 post shelve's aren't terribly expensive (the rack is, but i have 2 from gutting an office) - cover with oak panels and doors and she can have a bookshelf on the other side for books and pictures.
the rack is a good idea IMO because the shelves are adjustable; slits cut in for ventilation; will hold any console you can put on it (some of them are rated for 85lb) as well as any AV equipment you have
put a rack mounted network switch in there for the newer consoles and leviton (or amp, forget) makes patch panels with jacks that have rca / hdmi connections in them.
hell, score a rack mounted power distro block (Amp) and leave them all plugged in. go crazy and get a APC UPS - but those are pretty loud (by far the majority of the noise in my server room)
its gonna cost more than anything u can even think about getting from ikea or the like so this is gonna be a bit on the more extreme side.