Contra 4 review at Ars Technica.

"Let's forget everything in the Contra series except Contra, Super C, and Contra 3. Now, let's pretend that someone was going to make a sequel to the third Contra game, in 2D, using all the old-school weapons and taking notes from the classic level designs. That's basically what we have with Contra 4, a reboot of the series that takes many cues from the older games while still giving you a reason to play through. The question is, after asking for a game exactly like this for so long, are we sure that this is actually what we wanted?"

Full Source: Ars Technica via Gonintendo