I tweeted this deal first from @MileValueAlerts. Follow @MileValueAlerts on Twitter and follow these directions to get a text message every time I tweet from that account.

Delta is offering awards to London for 22,500 SkyMiles each way this winter. That is a 7,500 miles discount off the normal price.

The details are a little sketchy (just like Delta's lack of an award chart) because those listed on the promo page are incomplete and incorrect:
Origins & Destinations | Round-trip Award ticket and sale fares for travel from select U.S.

I tweeted this deal first from @MileValueAlerts. Follow @MileValueAlerts on Twitter and follow these directions to get a text message every time I tweet from that account.

Delta is having a "Pre-Black Friday Award Sale" for roundtrip awards that cost 20,000 miles roundtrip:

booked by November 30, 2015
flown January 5 to February 24, 2016 excluding February 12-16 and 19
with a Saturday night stay

Delta lists "sample cities" on the sales page, but not a complete list of discounted city pairs.

I did a sample booking from Cincinnati to Las Vegas for January.

There is fantastic flat bed Business Class award space for two people on Delta flights to Europe next summer for the Level 1 (on the former, now deleted chart) price

Korean Air releases amazing award space on its flights. Here is a post focusing on how Korean releases more First Class award space than any other airlines, and award space is similar in all cabins.

Despite both being in SkyTeam, Delta miles cannot book Korean First Class, which is one reason to focus on Korean miles. However Delta miles should be able to book all the Business and economy award space on Korean flights, since partners generally release all their Saver award space equally to all partners.

At the moment, this isn't the case.

Until November 17, 2015, the Gold Delta SkyMiles Credit Card is offering 50,000 bonus SkyMiles after spending $2,000 in the first three months, and a $50 statement credit after your first Delta purchase during the same period.

The normal bonus is 30,000 miles and no statement credit.

Contents of this article:

Offer details
My valuation of the offer
Are you eligible for the bonus?
Best uses of SkyMiles

Offer Details
The Gold card is the “standard” airline credit card.

50,000 bonus SkyMiles after spending $2,000 in the first three months
2 miles per dollar on

Delta operates a daily flight from Los Angeles to Honolulu and back on a 767 with flat beds in Business Class.

Update 8/20/15: Delta now advertises this fare sale and says the deals must be booked by tomorrow August 21, 2015.

This page also lists some of the fare sale city pairs, though definitely not all.

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Yesterday, Delta started selling awards to Europe for 21,000 miles each way in economy and 43,500 miles each way in Business Class. These are huge discounts off the "normal" price of 30,000 miles each way in economy and 62,500 miles each way in Business Class.