Done deal subject to a medical, announced on the official site last night.
Downing has been consistently good in the league for more than five years, whether as the big fish, small pond focal point of UEFA Cup runners-up Boro or outshining the more-hyped Ashley Young as Villa's Player of the Season last campaign.

For the fifth year running. Not for those with weak stomachs.
Points total after 19 games:
10/11: 25
09/10: 30
08/09: 42
07/08: 37
06/07: 34
Results over 19 games:
10/11: 7 wins, 4 draws, 8 losses
09/10: 9 wins, 3 draws, 7 losses
08/09: 12 wins, 6 draws, 1 loss
07/08: 10 wins, 7 draws, 2 losses
06/07: 10 wins, 4 draws, 5 losses
League position after 19 games:
10/11: 9th
09/10: 7th
08/09: 1st
07/08: 4th
06/07: 3rd
# of points behind 1st place:
10/11: -16
09/10: -12
08/09: +1
07/08: -10, with a game in hand
06/07: -13
Goals scored after 19 games:
10/11: 23
09/10: 36
08/09: 30
07/08: 33
06/07: 28
Goals against after 19 games:
10/11: 24
09/10: 25
08/09: 12
07/08: 12
06/07: 15
Home Goals:
10/11: 17
09/10: 26
08/09: 16
07/08: 20
06/07: 20
Away Goals:
10/11: 6
09/10: 10
08/09: 14
07/08: 13
06/07: 8
Clean Sheets:
10/11: 6
09/10: 6
08/09: 11
07/08: 10
06/07: 10
Goal scorers:
10/11: Torres 6; Gerrard, Kuyt, Maxi 3; Kyrgiakos, Ngog 2; Babel, Cole, Johnson, Skrtel 1
09/10: Torres 11; Benayoun, Gerrard, Kuyt 5; Ngog 4; Babel, Johnson 2; Skrtel 1
08/09: Gerrard 6; Keane, Kuyt, Torres 5; Alonso, Riera 2; Arbeloa, Benayoun, Babel, Carragher 1
07/08: Torres 9; Gerrard 7; Babel, Kuyt, Voronin 3; Alonso, Benayoun 2; Hyypia, Sissoko 1
06/07: Kuyt 6; Bellamy 5; Alonso, Gerrard 3; Crouch, Garcia, Gonzalez 2; Agger, Carragher, Fowler, Riise 1
# of games Liverpool failed to score in:
10/11: 5 [Wolves (h), Stoke (a), Everton (a), Brum (a), City (a)]
09/10: 4 [Chelsea (a), Sunderland (a), Blackburn (a), Pompey (a)]
08/09: 4 [Villa (a), Stoke (h), Fulham (h), West Ham (h)]
07/08: 5 [Pompey (a), Birmingham (h), Blackburn (a), United (h), City (a)]
06/07: 7 [Everton (a), Chelsea (a), Bolton (a), United (a), Arsenal (a), Boro (a), Portsmouth (h)]
Home form:
10/11: 6 wins, 2 draws, 2 losses; 20 points out of 30
09/10: 6 wins, 2 draws, 2 losses; 20 points out of 30
08/09: 6 wins, 4 draws; 22 points out of 30
07/08: 4 wins, 4 draws, 1 loss; 16 points out of 27
06/07: 8 wins, 2 draws; 26 points out of 30
Away form:
10/11: 1 win, 2 draws, 6 losses; 5 points out of 27
09/10: 3 wins, 1 draw, 5 losses; 10 points out of 27
08/09: 6 wins, 2 draws, 1 loss; 20 points out of 27
07/08: 6 wins, 3 draws, 1 loss; 21 points out of 30
06/07: 2 wins, 2 draws, 5 losses; 8 points out of 27
I guess it's not all bad news.