I'm looking into transfering a site that's on a .com to a .us domain that's substantially shorter. Will this negatively affect SE rankings? I've heard Google for example treats gTLDs like .us like weaker than .com?
I have several top ranking us domains - but they only target US traffic. If you are looking for International traffic, then you could experience negative effects (in addition to domain age) - depending on your niche.
^That's exactly what I'm afraid of. I wish gTLDs were treated equal to major TLDs. I simply chose to buy a premium .us domain only to portray that we are an American-based company, but I don't want to lose international business because being an American-based company is what makes our international consumers convert into customers, let alone convert into traffic.