Let me give you a sitrep:
Latest game discs come in XGD3 backup format require new firmware LT+ 2.0 (it is wrong to say ixtreme for that firmware is obsolete ever since 1.6) Today its called LT and LT+
Mini Q/A
1. What is this XGD3 format?
Some new disc format that has more data in it for MS to use for well more space and added security
2. Does this mean i can't play my 5000 LL games?
No not really, just be PATIENT.
3. Some guy told me about a JTAG what is it ?
A JTAG lets you run unsigned data so basically you can do whatever you please with your 360 - this even includes running games directly from the HDD (With no DISC inside) as well as running games from a External HDD via USB and even alows you to pirate XBLA and DLC !
4. Cool, should i do it ?
If you know what your doing go ahead, it needs some soldering experiance
5. Do you know anyone who does it ?
No.
6. Do you recommend it ?
No not really - you will more or less "frakenstein" your 360 it wont look pretty - also if piracy is your main goal then stay with a flashed drive .
7. I don't care about looks, can i still JTAG and be safe on Live
You will be banned within 3 hours of going online with a JTAG
8. So what shall i do?
Keep an eye on
www.c4evaspeaks.com - this is the hard working man/women/group that are the brains behind the reversed engineered DVD drive firmware, and they do it for absolutely free (and sold here at 25$ an update, 50$ for a fresh flash). Once you see the LT+ 2.0 become AVAILABLE go down to your favorite mod shop and request it - they will know
9. But dude im like dying to play gears can't they speed it up ?
No.
10. Well is there like a temporary fix to this, anything i can do
Other than a JTAG you can't play all new/XGD3 backup games - no fixes with such things.
11. I have on old xbox and everything is working HOW !!!!!!!???
You probably have a old Sammy or Ben-q drive - be proud - and also how on earth would anyone still have such an old console still alive, the ones i see the most these days are e74'd or RRoD beyond repair.
Long story short: Just wait. This C4eva is a stealth freak (he makes LT firmware as safe as possible on XBL) - he likes to like triple and even quadruple check his work
Hang out on the channels he is on IRC - they should be somewhere in the above link - there is also others who will gladly answer your questions
Be warned : The the 360 modding community is very arrogant - very.