After testing this card in a few different decks, I have come to the conclusion: don't be fooled by the yellow border, this is a Jinteki card.
Blacklist is one of those cards which is "fine" for value. It's 0 to rez and 3 to trash, giving you a small advantage even if it does nothing but force the runner to run it. The main value interactions are against Shaper recursion cards like Simulchip and Harmony AR Therapy, which are normally economically important to the decks that run them (sometimes even vital to their operation), but are blanked by Blacklist (thus forcing a run on Blacklist to trash it). Blacklist also gives nice value against heap breakers like Black Orchestra; they have to be installed manually, costing an additional click and a card (heap breakers are often discarded to hand size after accidental overdraw or to pay a cost, but if you can't use them after discard you'll have to use some other card instead).
All this value is very nice, but it isn't really worth a deck slot on its own; if you wanted a card that forced the runner to run it or else let you accumulate a slow drip of value, you might as well just use a drip economy card like PAD Campaign, or indeed any other economy asset with a fairly high trash cost. Rather, Blacklist is at its best when it's part of a combo. So what combos are available?
Blacklist can win the game by itself if you trash the runner's only copy of a particular breaker; for example, if you trash the runner's only fracter, you can put Blacklist behind any ETR barrier (say Vanilla), and the runner suddenly has no way to break barriers, nor to trash Blacklist, an advantage that can often be exploited for a forced win. It's far from unheard of for runners to use single copies of breakers, found with cards like Test Run (which also serves as recursion to recover from a trashed breaker). The main downside to this is, how are you trashing the breakers in the first place? The most convenient way to do this is from the grip, hoping to hit the breakers using random trashes; in other words, damage. So in order to set this combo up, you want a deck that naturally deals a lot of damage, but which doesn't primarily aim for a flatline (who cares which cards you trashed if the runner is dead?).
In the current metagame, MKUltra is one of the most widely played killers in Anarch decks; many Anarchs will rely on it as their only method of beating sentries, and even if they know they're about to encounter a sentry, they will typically attempt to install MKUltra from the heap (saving a click), rather than from hand. The heap install only works when they encounter the sentry, though; and there's a window to rez Blacklist during the approach, after the Runner has already committed to not jacking out (this is the same window normally used to rez ice). If you rez Blacklist in that window, the Runner will suddenly have no ability to install their breaker and will end up slamming face-first into your sentry's subroutines. Depending on which sentry you're using, this can flatline the runner, or at least set them back several turns.
(This trick is also possible, if a little less effective, with code gates; it doesn't work as well with barriers because Paperclip's MWL status means it often loses the deckslot competition with Corroder, and because faceplanting into a barrier is rarely harmful.)
Some damaging decks (especially those based on meat damage) are aiming primarily to win via flatlining. However, there's a second way to win via damage, the "thousand cuts" style (or in Netrunner's case, 45 cuts): if you can exhaust the cards in the Runner's grip and heap, they become unable to sustain any damage, or to draw up to buffer against future damage, and will become helpless against whatever it is that you're using to inflict damage (whether traps like Snare!, ice like Kakugo. or identities like Jinteki: Personal Evolution). Most runners are prepared for this sort of deck, with a common counter being the use of mass recursion cards like Harmony AR Therapy and Trope to buy additional time. Blacklist acts as a counter to these counters, ensuring that your thousand-cuts strategy can work at full capacity.
There's an obvious natural synergy between these combos: Blacklist is thus at its best in a deck which does a large amount of damage in small quantities over the course of the game, without aiming for a flatline combo (or with Blacklist itself as one of the main flatline combos), and which contains at least some sentries/code gates with a large facecheck penalty (I like Saisentan and Anansi for this). That sounds like net damage to me, and in particular it sounds like a common core strategy for Jinteki decks. (You could perhaps run it out of Weyland Consortium: Builder of Nations too, but I haven't tested this.)
I think Blacklist is best as a 2-of in this sort of deck, giving you a high chance of drawing it by the time you need it. Going to 3 is probably too much: sometimes, the runner will have no targets for it (this happens with some Criminal decks), so you don't want to be flooded with Blacklist copies. (That said, it still has some use in these circumstances: you can follow the normal procedure for otherwise useless assets, of dropping it unrezzed into your scoring remote in the hope of baiting the runner into running it, something that works surprisingly often.) However, against Anarchs who use heap breakers, or Shapers who rely heavily on recursion, it has a decent chance of winning the game by itself, often games you couldn't have won without it. Given that that describes a large proportion of the runner metagame at the moment, Blacklist is definitely worth the deck slots when you play it for the combo. At only 1 influence, it shouldn't be hard to pay the deckbuilding costs, either.
