I believe that a few months ago, when the offers you mentioned were made, the highest sign-up bonus for Star Alliance miles was 50k. Since then, there have been several good deals since then that broke that 50k Star Alliance miles barrier, most having a "mistake" component similar to Citi allowing you to apply for all three cards if you timed it just right.

1. Chase Sapphire briefly allowed double dipping in sign-up bonuses to obtain 100k points.
2. American Express Membership rewards has issued many targeted rewards for 75k and 100k sign-up bonus for a number of Membership Rewards cards, most of which waived the annual fee, and AmEx was, for a while, allowing untargeted people to "bump" up to the offer that they were not targeted for by applying under a different offer and then calling in with the promotion code that they weren't targeted for. The heyday seems to have been a few weeks ago, when AmEx was also allowing people to call in and add a substantial bonuses for adding additional users and making a certain number of transactions per month. Since then, AmEx has tightened up on the most generous of those offers. I believe that it was briefly possible to work these deals into 175k bonus points, which I think were convertible at greater than 1:1 on Star Alliance by using a redemption special to Air Canada, or much greater by redeeming to Delta (not Star Alliance).
3. thepointsguy.com mentioned that there is a targeted 60k miles offer for the United credit card.
4. Fidelity offers for existing customers have been expanded to include both Delta (not *A) and AmEx Membership Rewards (redeemable to *A via Air Canada and, for a few more weeks, Continental), although there appears to be a little bit of a crackdown on the most egregious cases of people not keeping their qualifying deposits in their accounts as required by the letter of the offer, although "most egregious" in this context seemed only to include people who had the nerve to call into customer service in the midst of abusing these offers in some obvious way, although it has been a couple of weeks since I last looked at the thread on that offer.

There are also a few non-airline offers out there that could be worth over $1,000 per credit card application: AARP 5% rebate for first 6 months, and three offers involving supermarkets or drug stores that may be expandable to most other spending by buying $500 gift cards for a ~$5 activation fee: 6% supermarket rebate from AmEx Blue Preferred ($75/year annual fee), 5 ThankYou points/$ on supermarkets and drug stores (and gas stations) from an offer from Citi Preferred, and a rebate of up to 7 points/$Rite Aid from Capital One Venture Rewards (2 pts/$ standard + 5 pts/$ bonus if you "activate" the offer on the cap1 web site; most Rite Aid's do not allow purchases of gift cards by credit cards, but there may be some exceptions).

There also have been a little bit of tectonic creep in the prepaid card landscape: AmEx e-gift cards (potentially stack another 1.6% big crumbs rebate on your onlnie orders, but I'm apparently banned by the for the moment), and AmEx for Target (currently being tested in a few cities, facilitates earning a small amount of rewards on up to $400/week in ATM withdrawals, mostly a psychological comfort for people irked by losing the opportunity to earn points when required to pay in cash).

So, I think the FlyerTalk economy is continuing to do OK, although loss of the mint was a big blow.