Sounds like you're getting the phone for yourself hah

 

Here are the big differences from the Atrix 4g and the Inspire 4g
Inspire 4g
weighs 163.9g
Lower resolution, but bigger screen 480 x 800 pixels, 4.3 inches
Has Dolby Mobile and SRS sound enhancement
4GB internal storage with 768MB ram
8MP camera, duel LED
1Ghz Scorpion Processor
FM Radio
Cheaper Price

Atrix 4g
weighs 135g
Better resolution, but smaller screen 540 x 960 pixels, 4.0 inches
Gorilla Glass display with fingerprint reader
16GB internal storage with 1GB ram
5MP camera
Dual Core 1Ghz ARM Cortex Processor, Geforce GPU!!!!
Active Noise Cancellation
HDMI Port
Better Battery Life

Basically the Atrix 4g is a more powerful phone than the Inspire with a little bit more features and lacks some stuff from the Inspire like a better camera and no FM radio....in which most people will probably listen to MP3s or Pandora anyway

 

Infuse?

 

The HTC Holiday is only rumored, but it sounds like it will be a huge phoneAt&t doesn't have many Android phones that are great, I honestly find the Atrix to be the utmost best one, if I was on Tmobile, I probably would have hopped onto the G2X

 

Well if your g/f isn't the geeky type, then she may prefer the Inspire. My wife loves hers over my Atrix, but she absolutely loves the Swype that my Atrix has and hers does not. So if your g/f texts a lot it might be something to consider. The HTC Inspire's "Sense" is a nice launcher, hands down better look/feel than the Atrix's blur or whatever and Launcher Pro+ on the Atrix is just ok, bought it, not overly impressed but it's ok.

If the phone is for you secretly, then yeah dude, no question asked the Atrix is the way to go.

 

Since you already have an Atrix and your gf wants a new phone, and you want to play with a new phone, might as well get the Inspire

 

One thing you may want to consider: if you want to video chat with her, FFC.

 

The Infuse has a front facing camera. Plus it's something brand new to play with.

 

should have just got the infuse and gave her your atrix haha

 

Good choice either way.

 

The Holiday is absolute garbage.

If I remember correctly the Holiday doesn't have multi-touch, meaning it can only recognize one finger on the screen at a time. You won't be able to play any games on it or use any programs that require two fingers.

 

I think you have the wrong phone. The Holiday is only a rumour phone with very little information leaked.