With regard to class changes... consider this patch "progressive". Well I would hate for it to be regressive!

I'm going to be a bit cautious in what I say in this regard. Will there be some changes to classes? Yes, there will be some. We're not rushing into a bunch of class changes for this patch at this point. Consider the patch to be a bit more progressive in nature. As we go along, the developers are going to be keeping a close eye on the results of any changes and additions and then making changes as they feel they are necessary. How many changes occur are going to be based on testing over time. This is why it's important for players to get in and test it as much as possible.

We want to make sure that the changes we are making are viable and practical for continued balance of the classes and don't want to put in too many changes at once and essentially skew the results too much one way or another. 

2.4 Patch notes are starting to come in slowly, here's a good summary from the people at MMO-Champion.

Patch 2.4 will be announced when Blizzard are ready, thank you very much!

I think people would get tired of hearing "not today" and start asking "when?" Then I'd have to answer with "soon" and it would just go on from there.

Things are in the works, the cogs are moving, and we'll get there.

Here's a list of the known issues in the 2.3.3 patch (it continues after the jump!):

General
- Dwarven racial Find Treasure is deactivated on death.
-Undead Males main hand weapon is appearing larger than previous builds.
-Equipping a thrown weapon while in the middle of an Auto-Shot will cause animation issues.
- The Gnome racial ability Escape Artist does not remove the Unstable Cloud debuff.
- Deleted characters take up space in an arena team.
-Male Blood Elves do not blink.
-The Gnome racial ability Escape Artist does not remove the Unstable Cloud debuff. 

The PTR forum has been cleared, does this mean 2.4 is coming?

To keep this forum relevant to the current or upcoming version on the PTRs, all old threads have been removed. This will be done soon after each patch test cycle is completed and the patch is applied to the regular realms.

Informational sticky threads will be reposted after each forum wipe, and as new information about the current or upcoming patch becomes available it will be added in this forum. 

From a blue poster on the forums:

We have information in the works, but I'd caution people that it's not going to be today or even Monday, but we have plans and are working to put things together that will hopefully make the wait worthwhile.

I'd also caution people about getting their expectations up in regard to "sweeping class changes". Again, we have many things in the works and a definite plan of action that we will share with you all more as we progress.

As always, I'll remind people that if we don't post patch notes, they aren't the real deal. We create them, we post them, we make them reality. Don't supplant someone's fantasy patch notes for the real ones in your heads. It will only end in tears on so many fronts.

Patch 2.3.3 is apparently going to be deployed on the live servers...

General

• Some players may notice improved data load times when newly entering the world and after zoning into new areas.
• Character/NPC load times have been decreased, and now should appear faster. You’re not hearing voices, there really are people in Shattrath!

• Felspine the Greater in Shadowmoon Valley will no longer evade when engaged.
• Guttripper in Nagrand will no longer evade when engaged.
• Players will now be correctly credited with their arena points if they purchase an arena item during weekly arena calculations.
• Using a castsequence macro on a target moving out of range will no longer cause it to stop working.

• Dwarven racial Find Treasure is deactivated on death.
• Undead Males main hand weapon is appearing larger than previous builds.
• Equipping a thrown weapon while in the middle of an Auto-Shot will cause animation issues.
• The Gnome racial ability Escape Artist does not remove the Unstable Cloud debuff.
• Deleted characters take up space in an arena team.

A good summation of everything we know about patch 2.4:

Patch 2.4.0 will be the second patch of 2008, and most likely the last one before the release of Wrath of the Lich King. The main feature is obviously the new Sunwell Isle and the two new dungeons, Magister's Terrace (5-man) and Sunwell Plateau (25-man).

There are currently no plans for a 2.5 patch...

Right now, we're focused on patch 2.4 and nothing beyond that is currently planned. Time will tell, however.

We've announced some major features, and hinted at things we'd like to do for 2.4, but that's about it currently.

Some big changes are coming to the way the UI is coded in patch 2.4, so they set up a proper thread in the forums to document them. Here's what's there so far:

Significant Changes
* The combat logging mechanism is completely overhauled with explicit data instead of text strings delivered to the UI. See slouken's post below for a sneak-peak at some of the current details. Highlights include detailed flags indicating relationship of involved units to player, unique identifiers for units with the same name within the combat log -- great for log analysis.

Visual Settings
* There's a new cVar unitHighlights; 0 = no model highlighting with Alt-Z, 1 = model highlighting on with Alt-Z. (e.g. /console unitHighlights 1)