48 Seats, Give Or Take A Mile

Silver's updated prediction:

Republicans are given a 73 percent chance of taking over the House, up incrementally from 72 percent last week. During an average simulation run, Republicans finished with 227 seats, up from 226 last week; this would suggest a net gain of 48 seats from the 179 they hold currently.

... [The] consensus [among forecasters of around a 50-seat Republican gain] ... is somewhat misleading because it does not adequately capture the fact that there is considerable uncertainty on either side of that 50 seat estimate, more so than in past elections.