Clarification: Both of us would be dropping the Verizon Galaxy Nexus for T-Mobile.
Also - most important question of all: White or Black?
Do you have an unlimited data plan on Verizon? If you do, you can sell your plan for a lot of money or give it to another family member/relative. Verizon doesn't offer unlimited data plans anymore, so they?re very valuable.
If you?re upgrading from the
Verizon Galaxy Nexus to the
Nexus 4 on T-Mobile, there are 3 things you need to keep in mind.
First, you will lose Verizon?s vast network coverage and LTE. You will have to settle for T-Mobile?s smaller network area, and you won?t have LTE unless you flash the radio. Hopefully T-Mobile?s DC-HSDPA will be fast enough for you. (It probably will be sufficient for most tasks.)
Next, you will have less internal storage on the Nexus 4 (16 GB versus 32 GB). You should delete stuff on your Galaxy Nexus until you reach 16 GB or less, then see if you can live with the results. If you can, you?ll do fine with the Nexus 4.
Finally, you cannot swap the battery on the Nexus 4 like you can on the Galaxy Nexus. There is also no official extended battery (again, unlike the Galaxy Nexus). However, the sealed battery is slightly larger (2100 mAh versus 1850 mAh). If you disable Google Currents, don't install the Facebook app, and don?t max out the screen brightness all day, you should get a day?s worth or more of battery life.
(I should also mention that the headphone jack is on the top of the Nexus 4 instead of on the bottom, like on the Galaxy Nexus. You can rotate the screen into reverse portrait mode to magically put the headphone jack at the bottom if that sort of thing bothers you. On-screen buttons FTW!)
As for the color? you should get both white and black so you'll have a complete set.