T-Mobile G2x, is not. We can't even say for certain whether or not the updates confirmed by LG Singapore are just for those particular models in Singapore.
About a couple of weeks ago, a tweet from LG confirmed that the LG Optimus 2X would be updated to Android 4.0, but only in South Korea. The tweet noted that the update was still being tested. Before that, LG Canada confirmed the update for LG Optimus 2X owners in that country. LG Optimus LTE owners in both South Korea and Canada were also told to expect Android 4.0.
Frankly, the way that LG has informed customers and others about its plans for the Ice Cream Sandwich updates has not been clear. Instead of having LG regional offices make statements, one dispatch from the suits in South Korea could clear up any confusion.