My stab in the dark guesses are based on polling patterns, betting odds, tactical voting assumptions, incumbency advantage, boundary bias, the SNP surge and total guessing:-
Vote % and Seats (Total 650);
1) Labour 34% and 277 seats
2) Tory 34% and 276 seats
3) SNP 4% and 45 seats
4) Liberal Democrat 10% and 28 seats
5) DUP - C.1% and 10 seats
6) Sinn Fein - C.1% and 4 seats
7) SDLP - C.1% and 2 seats
8) UKIP - 10% and 3 seats
9) Plaid Cymru - C.1% and 2 seats
10) Green - 2% and 1 seat
11) Minor - 4% and 1 seat
12) Spoiled - C.1%
I think the Political Betting blog notes correctly that -
"Because it is clear that many are not voting for their allegiance winning the national aggregate vote will mean less. The election is about seats.
If the Tories are not the national vote winners you can see them pointing to places like Hallam and Scotland to suggest that those figures are less meaningful in the likely post-election legitimacy debate.
This is a direct product of first past the post. If people want to make their vote count then they might vote differently so adding up national vote totals doesn’t tell you as much."