Oh boy! Something I can speak authoritatively on: being in trouble with a woman!

The reason the other gents keep saying 'jewelry' is that if you *EVER* cross the boundary where there was something that she really wanted and you got her something that's more of your thing, it gets dire and dramatic. Even the coolest ladies have a low level of that in the back of their minds, whether they know it or not (you just may never see it if it gets appeased easily). Seriously, but a little room in the budget for something that looks nice, even if it's not that expensive.
Now, to the camera. If this is for HER and it's truly what SHE wants and it *IS* a PRESENT, don't buy used or refurbed; yes, it's conservative and makes sense, but it's just not a gift if it's used. Again, if it's for her, get her something NICE -- which means features that she may want or use . . . unless she told you she wants to go pro and shoot in manual mode, this means a T2i, T3i, 60D.
The one part I would urge you to reconsider is putting her on a prime -- get her some nice glass (used for that is fine if you got a new body). Before buying, Craig (CR Guy) was nice enough to respond to an e-mail suggesting the EF-S 15-85mm f/3.5-5.6 IS USM which was a great all-around lens that allowed me to grow quickly. If she's going to want to shoot babies (that still sounds silly when I say it), the EF-S 17-55mm f/2.8 IS USM would probably be a better choice. Again, if it's for HER, you may just have her stick with the kit lens and give her an IOU on a nice prime/L glass or a nicer EF-S lens.
All that said, what is your timeframe? The lower-end DSLRs had some awesome deals during last November due to Amazon and Newegg going at it and the T3i will probably be ultra affordable during that timeframe.
Either way, congrats and condolences

Life is never dull when you're married.