Probable LTE Nexus 4 passes through Bluetooth SIG13
The original Nexus 4 had an LTE radio, but it was never certified for use, and so the only way to get it working was with some hacking. It looks like this model won't require anything so extreme. Yesterday, the Bluetooth SIG saw a filing for an LG device labeled as "LGE LTE Mobile Phone LG-E960"; and, the interesting bit is that the original Nexus 4 was model LG-E960.
That seems like as close to confirmation as you can get without an official announcement. Of course, that leaves the real question of the price. Assuming the Nexus 5 will be in the $349 price point as seen in the Play Store listing, that would make it seem like the LTE Nexus 4 would likely keep the pricing that the original saw at the end of its life of $199 for the 8GB model, and $249 for the 16GB model. It is possible that would mean the Nexus 5 would start at $299 for an 8GB model, but Google could leave that out and have the $349 16GB Nexus 5 as the base new model.
*Update* It turns out that there is evidence that this may have been a sloppy posting by the Bluetooth SIG. So, we can't reasonably assume that this is confirmation that there will be an LTE version of the Nexus 4. However, there are still questions as to why this filing has surfaced, so we'll continue to monitor the story and see where it goes.