When one of the most vocal activist investors in the world gives you three thumbs up, it's hard not to blush. That's probably what Target Corp. (NYSE: TGT) executives are feeling right now, as William Ackman acknowledged to Bloomberg News that Target is "probably the best retailer in the world.''

That's quite a dose of praise from Ackman, whose Pershing Square Capital Management investment company increased his stake in the nation's second-largest discount retailer back in the summer. Meanwhile, Target shares have fallen 15% since that time, but that isn't phasing Ackman at all.

Ackman, who has pressured the likes of McDonald's Corp. (NYSE: MCD) and is currently pressuring Sears Holdings (NYSE: SHLD) for share price gains, apparently likes Target very well. Pershing Square now holds 9.6% of Target through shares and options at this time, as as Ackman says, "We have enormous respect for management ... they are doing exactly the right things. Low income, upper income, millionaires, billionaires like shopping there. It's got a universal appeal. It's got incredibly high-quality products.''

That's quite an endorsement from an investor who squeezes hard when the going gets tough. Target's operational and sales environment must not be that tough at this time.