Yeah, we definitely need one following van Persie's departure.
I was one of those, perhaps in the minority, that thought RvP still had a lot to offer and he is a better player than he's shown the last two seasons. A lot of it stems from motivation IMO, as others stated, he seems half-arsed and disinterested so often last season. If he could reinvigorate that desire he would have provided sufficient cover for Rooney and perhaps even displace him upfront. He's still a good player.
However, he's obviously off and now a striker is definitely needed. I'm hoping that we already have one lined up, but it wouldn't surprise me if that's not the case and LvG/Woody, just want him off the books as soon as possibe. Hernandez is the very definition of a super-sub and perhaps more suitable to bring off the bench than RvP, I just have less faith in him and still rank him comfortably below RvP.
Not sure who we can bring in though. Will we end up shopping around the lower tier of strikers, just to appease Rooney and not shift him back into midfield, or, will we sign a marquee striker that displaces RvP, keeping in theme with LVG's ruthless transfer strategy approach thus far.