Same here, I already got 4g on my phone to share with the vita.
I was honestly a little burned with the 3G bundle. I would of bought the WiFi but at launch they offered 3G, stardust delta, 8gb memory card for $300. For the game and the memory card, it was worth it for me to put down an extra $50. Then when I got it, there was a disclaimer that said stardust delta was only given to you AFTER you subscribe to ATT data plan and use up your free month. Well, ATT has horrible service in my area, the data plans are horribly priced (and capped for downloads), so I didn't sign up for it. My own fault I paid more and didn't even try getting my "free game" for the extra money paid.
Anyways, on topic, I'm not mad about a 4G model (if rumors are true). I never planned to use the 3G on my vita but I like options to be available to me if I ever change my mind. To top it all off, I just tether my vita to my phones 4G and play online from anywhere
Upset? Nope, as I have had my Vita for a year. Pleased if they allow networks that are not AT&T as well? Exceptionally, since AT&T has no 3G presence where I live, and barely any 2G.. I might be a little sad because I would have to kill off my PSN on one of my Vitas then, though. but I am sure it would become the go-to platform for any CFWs that should happen.
I got the 3G at launch because it was cheaper than the wifi and included an 8GB memory card. I never activated the 3G (not even sure if I can here in Canada) and I wouldn't anyways because it's useless. Don't care about 4G either, it's equally useless.