But they're also capable of terrible duds: if their tie against the Bengals and blowout loss to the Ravens seem too long ago, look no further than their week 16 10-3 loss to Washington.
Playoff football is often about the team on a hot streak; games from earlier in the season don't matter as much as how the team is playing recently. The Eagles look hot after their 44-6 week 17 win over Dallas, but that Washington game was just a week earlier.
The Eagles have struggled in close games this season: they're 1-5-1 in games decided by seven or less. Andy Reid has been criticized for some of his decisions in close games; if the Vikes keep it close, the Eagles could choke it (but then everybody else relies on the Vikes to choke when it matters, so don't get too excited).
It will be a tough game for the Vikings to win, and they could get blown out by a very talented Eagle team. But in Thunderdome (hopefully the crowd is energized for the first home playoff game since the 2000 season), it's a winnable game against an up and down team.