Some of my own speculation of why they aren't releasing the mod-source for both TF2 and L4D are: - The stats/achievement thing: I can imagine someone with access to the source would be able to make a certain mod which can fool the stats/achievement system, and as such someone can 'cheat': For myself, I don't put too much pleasure in unlocking them that way, but I can see how people would to cheat with enhancing their E-peen (so imo, a half-valid option). - Afraid of people actually creating new content that can rival their next product: This is especially the case with L4D, whereas I can see that some of the things they're talking about in releasing in L4D2, has been stuff that me and a couple of my mates have been planning to actually do with L4D (but got severely disappointed at not seeing the source released). If this is one of their motivations behind this move... I can only be very disappointed. - Valve considering the HL2-source to be enough to release to the public, as in the end, simply said, TF2 and L4D are only enhanced modifications of the Source-engine. Again, if this would be the case, I severely disagree, as L4D has several components which are fairly unique to that game, but beg to be enhanced/explored in modifications.
I think #2 gets closest to what I consider to be the reason behind this - mods to multiplayer online games such as TF2, L4D and CS:S would fracture the player base.
On the PC side, I can't remember the last good RTS or RPG that came out that played exclusively/best on PC.
This is the only part I have to disagree with, at least as far as RTS games are concerned. I can't think of a single console RTS game that performs as well on a console as it would on PC because consoles lack a decent control scheme.
Two recent, somewhat well-received console RTS games that come to mind are Tom Clancy's End War (which made use of voice-activated commands on Xbox 360) and Halo Wars (ugh). Either one would have benefited from a better control scheme. You mention mouse and keyboard support for the current console generation, and for all I know these games may have support for KB/mouse...I just think the average console user wouldn't bother.
The review also notes that these programs support Silverlight, the partially open-source technology that is meant to go up against Flash."It's hard not to see Expression Studio as less a true 'suite' than a collection of products that have been co-branded after the fact — partly because Microsoft's other suite, Office, is so tightly knit in comparison. It's tough to see how the products in Expression Studio fit into a single integrated workflow or how they can all be used together, aside from creating XAML applications for Web sites.
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