My rule for investing in gTLDs is fairly simple: The more GoDaddy -- a $138M company -- appears to be embracing it, the more likely it will succeed.
I envision the domaining industry's GDP as a gigantic pool with a fat pipe leading in and another trailing out. Liquidity can travel along one of three trajectories:
(a) Out of the pool: This generally occurs when winning domains at NameJet/SnapNames auctions, with purchasing of speculative TLDs like .tel, with backorders, and with hand-registrations.
(b) Within the pool: Mainly comprised of domain-to-domainer transactions.
(c) Into the pool: This occurs primarily with end-user sales.
New gTLDs will naturally crash unless the amount of cash they cause streaming through the IN pipe, in form of end-user sales, equals or exceeds the cashflow domainers pour through the OUT pipe.
GoDaddy has perpetuated the lion's share of public awareness regarding the significance of domain ownership. By spreading this awareness to the masses through their sexy and bountiful advertising campaigns, GoDaddy is indirectly responsible for many, if not most, of end-users sales that have gone down; and those end-user sales represent the injection of liquid capital through the IN pipe that lends life support to the domain industry -- all our decisions, good and bad. Sitting in GoDaddy's back room is a pack of marketing geniuses. No parallel to these geniuses exists on any other registrar's board. Therefore, when GoDaddy embraces a gTLD, I take heed. When they choose not to, I eye that gTLD with cautious scrunity.
On running a given domain through GoDaddy's name checker, the first five gTLDs listed are .com, .net, .org, .info, and .me (I consider .me a gTLD for a slew of reasons) . The first four have firm taken root in public consciousness, and .me is quickly doing so as well. Why? Not because there's anything extraodinary about .me, but because GoDaddy -- our most powerful suction force through the IN pipe -- has chosen to spread a conflagration of public awareness about .me, more so than the have with any gTLD since .info (which GoDaddy helped popularize through its 99-cent registrations).
Armed with this logic, I am 100% certain .me is the only recently-introduced gTLD that MAY attain broad global awareness over time. The same cannot be said about .pro, .asia, or .tel unless GoDaddy re-examines its attitude towards these gTLDs, but I doubt they will.