Blizzard released v1.09 for D2 and D2X in late August, 2001.  D2X was in v1.07 when released, and v1.08 came out shortly after the game, with numerous bug fixes, but very few content changes.  v1.09 made tons of changes mostly to items, but had a lot of bug fixes as well, and general game improvements.  Since v1.09 was released, there have been v1.09b, c, and d patches, all of them fixing various bugs.  In addition to these actual patches, Blizzard fixes small things all the time on the realms, in addition to fighting hacks and cheats and such.  v1.10 is going to be mostly gameplay fixes, but exactly what it will feature isn't known.  Blizzard has mentioned a lot of potential changes, but as always with their patches, exactly what's going to be in them isn't known until they are actually released.

We had hoped to get more info on v1.10 at E3 in May, but no one working on D2X was at the show.  (The D2X patch team now is very small.  Very small. AKA, "him".)  We've had a few email exchanges about it since E3, and gotten some more info, but as always, Blizzard is cagey about admitting to anything before they do it. We had virtually the entire v1.09 readme posted well in advance, and that proved annoying to Bliz since they felt somewhat locked into making changes that had been confirmed, and didn't have the flexibility they would have liked.  So they're sharing less info with us this time around.

What are some major gameplay changes?
Some of these have already been listed (scroll down this page to see previous updates), others are new.

Monster changes:

• The 50% physical resistance for every monster on hell is gone.
• Monsters will have massively-modified resistances, hit points, damage, speed, AI, and more. This means they'll have at least double the hit points in many cases (to offset the removed 50% physical resistance) and much more higher/more variety in their resistances.
• Many monsters will have modifications to the AI.  They might not be so easy to distract with a minion or merc anymore.
• Monsters will spawn with far greater randomization, especially in Act 5.
• Random bosses should be more numerous.
• Drops will be tweaked, especially for the easiest/most run item droppers (like Pindleskin).
• Attack rates will be tweaked.  Ranged attackers will likely fire faster, for example.

Skill changes:

• No nerfs!  The plan is that no skills (or very very few) will be lowered in quality.  This doesn't mean they'll all work just as well as they do now though, since monsters might become much tougher.
  • (For a hypothetical example: If everything in hell goes up to at least 33% fire res, and doubles in hit points, then Firewall, Meteor, etc would seem weaker, even if the actual damage stats didn't change at all.)
• Skills might have more secondary changes (like the druid wolf/bear summoning skills, where adding to one boosts another).

Will dupes/hacks/cheats be fixed in the patch?
We don't have any more information about this.  As far as we know Blizzard is doing all they can to stop cheating now, so we don't expect any big changes in v1.10.

Who is working on the patch?
We can't name names, but the current patch team is two guys at Blizzard North, with the main programmer one of the core D2/D2X team.  The other guy was added more recently, and is handling the item changes.

How many new items will there be?
Our initial estimates of just a few here and there are probably low, considering how much work is being done to the skills and monsters and other such things. We can probably expect dozens of new elite uniques, and quite a few new runewords and crafting recipes as well. 

What about a leech penalty?
Since the 50% physical resistance is being removed in Hell, if monsters don't have any physical res, but are double the hit points (hypothetically) you'd need the same number of hits to kill them, but would leech twice as much, making mana leech very easy to have enough of, and making it far easier to keep your red full.  Something will be done about this, most likely a 1/4 or greater leech penalty in hell.

Won't things be harder for spell casters?
Probably.  Monsters will all be increasing in hit points, at least in Hell, and will likely get a lot more varied and higher resistances.  

What's going on with the Cow Level?
Nothing more is known about this than we said in the earlier update.  It will be "fixed" in some way.  Whether that means cutting the exp greatly, only letting characters do it once per difficulty level, making the cows have a wide variety of immunities, or all of the above is unknown at this point.  It will definitely not continue to be the great easy exp treadmill of D2X though.

Does Starcraft Ghost affect the patch development speed?
Not at all. Blizzard isn't a huge company, but they have hundreds of employees, and are working on multiple games at once.  SC Ghost is one of them, but one of the smaller ones, with Nihilistic doing much of the programming and graphics.  No one from the (very) small D2X patch team has anything to do with SC Ghost, as far as we know, and since Bliz has been working on SC Ghost for over a year before announcing it, it being known publicly now has no effect on the amount of people required to work on it anyway.  More discussion of this and other aspect of SC Ghost can be seen in this offsite article, and you can discuss SCGhost with other fans.