Here is a list of the items addressed, and the new content, that will be included in the 1.30 update (listed in no particular order):

Bf 109E altimeter now displays the km index

Bristol Beaufighter Mk I aircraft have been added; four flyable liveries are available

Cant Z.1007bis flyable model is now selectable in the aircraft menu

Fairey Fulmer AI only aircraft is no longer selectable in the aircraft menu

Hurricane BG.707 now displays the textures at the wing root correctly

two of the Maryland AI aircraft, one appropriate for Malta and one appropriate for the Western Desert, have been made flyable by adding a virtual cockpit; the cockpit is not historically correct but looks appropriate; the flyable Marylands have been added because of the desire to fly them expressed by the community; we just ask the community to remember the Marylands were not meant to be flown in MAW and are therefore of low quality in certain player position views

P-40 cockpit eyepoint and orientation corrected

P-40 turn and slip indicator corrected

custom cutscenes and UI animations have been added for the Royal Navy (britain_faa) and Italian nationalites

the Union Jack (b_flagpole_army) has been added for display by some ground unit facilities which would normally be under Army control rather than RAF control

new Malta campaigns for 1940 and 1941 have been added

an updated version of the North Africa 1941 campaign is included which adds two Fleet Air Arm aircraft (Sea Gladiator, Martlet) and the Beaufighter

the "Training" missions tab in the UI has been renamed to "Multi-Player" so the training folder can be used as a convenient place to store your multi-player missions
several facility names were updated for better display in the game

the air raid siren, included in many facilities, is now functioning correctly

SL (searchlight) facilities have been added for easier placement of single blue or single white searchlights in missions

other new facilities were added to support the campaign spawns

11 new missions have been added

ship service dates were reviewed and some were cloned for better spawning support

some ship names were updated for better display in the game

ships were organized so stock spawns will use generic names where as in campaign mode spawns will use HMS and RM names as appropriate (there are also a couple of new ship_ spawn control files that will let you use these configurations in missions)

a continuously submerged submarine, which fires torpedoes at nearby ships, has been added for creating additional mission complexity

the stock UI music has been replaced

the remaining custom spawns for the Greece and North Africa campaigns have been added

a new set of custom spawns to support the Malta campaigns has been added

spawns missing required mission goals for the campaign mode have been corrected

the random air spawns for the campaigns have been adjusted for a better balance during game play
ship formations spawned in campaign mode now move and shoot at enemy aircraft regardless of where they're spawned in the theatre

the Spawning Configuration Utility has been updated to support the Malta campaigns; at the same time, the selections for the Balkans, Greece & Crete have been combined since these regions are all within the existing Greek campaigns

all non-MTO related and fictional pilot biographies have been removed

all pilot photos have been updated and now display correctly in the UI

some pilot biographies have been updated with additional information

four new pilot biographies have been added for the Luftwaffe

four new pilot biographies have been added for the USAAF

new 1.30 splash screens

some vehicle names have been updated for improved display in the game

the Pzkpfw III-H main gun now fires

three new mines have been added for creating additional mission complexity: anti-shipping, anti-tank and anti-vehicle mine "vehicles" have been added which can be placed individuatlly using their corresponding facilities; a fourth facility (land_mines) has also been added to allow you to place a large mix of anti-tank and anti-vehicle mines at once

It is at least a week away before making the download available to the public.  This will be the last update targeted specifically at Chapter One.