Ok, the official Cupcake OTA has arrived, if those who don't want to wake anymore longer from the google push can actually download the update file and get your G1 mutated manually.

You may find the file(signed-kila-ota-148830.de6a94ca.zip) over here : Cupcake downloand, look for Cupcake 1.5 under T-Mobile OTA.

The procedure to update (for unrooted only) user: update with OTA files
For those rooted user, guess we will wait for JF to mod it first....

Happy Cupcake-ing!! ^^; 

PS: Dun blame me if you brick your phone during the procedure hor!!  , and make sure the batt is above 70% when proceed with the update.

thx for the update~
will try it out later

Congrats!! First OTA T-Mobile Cupcake user ^^;
Heh! tthe VK is just accessories to me, maybe for some short SMS replying.

Hey Ben, if possible please report the battery drainage ya!!

Hmm... seems like it took about 2-3 minutes to download the 37+mb Cupcake. Pretty fast eh.
If not mistaken, Schroddy_Cat also got the update and download less than 5 minutes over WIFI. But his problem is no signal with the cupcake even after a factory reset.

It looks like the update package is corrupted during downloading (suspecting only)....Guys make sure you got strong signal (wifi/3g) before performing the OTA update.