I was in the same situation, here are my thoughts on the issue.
There are major players on both sides of the argument:
HD-DVD : Microsoft, Toshiba, HP (who recently came over to HD-DVD by virtue of beginning to offer an HD-DVD drive on their PC's for $100.00 extra, LG etc
HD-DVD Studios : Paramount, Warner Bro's, Universal, Weinstien, Studio Canal
Blu-Ray : Sony, Hitachi, Mitsubishi, Sharp, Samsung
Blu-Ray Studios : Sony Pictures (including MGM/Columbia TriStar), Disney (including Touchstone, Miramax), Fox, Paramount, Warner, Lions Gate
Blu-Ray's list looks a bit more stacked to be honest, but there are a few issues that are still being worked out in the BR camp, some of which are making the studios seriously consider (Disney is the BIG rumor right now) HD-DVD...the biggest being saturation. The big "suprise" coming out of the PS3 launch is the very low attachment rate of movies to PS3's. There have also been some complaints about Blu-Rays video quality, which is mostly being blamed on the fact that they are still using MPEG2 compression vs VC-1 which is what HD-DVD uses. Audio is pretty much even however, with both formats supporting Dolby TrueHD, DTS-HD, Dolby Digital Plus, Dolby Digital, DTS-ES. Price for the players beyond 360 and PS3 is also a concern, with HD-DVD being a bit cheaper to purchase than Blu-Ray as well.
After seriously considering the factors, I went ahead and purchased the HD-DVD add-on for the 360 with the simple mindset that if HD-DVD wins out...cool. However, if Blu-Ray wins out...it will take at least a few years to do so, at that point the PS3 will be readily available and much cheaper than it is now. If Blu-Ray wins out, I will pick up a PS3 along the way...but why deny yourself HD-DVD now especially since it can be had for @ $200.00 bucks. I think the play MS made with releasing the drive seperate was quite a savvy move. The drive will have a 100% attachment rate for HD-DVD movies, thats all its for....I think Sony made a mistake in not making PS3 with Blu-Ray optional (the disc space is NOT needed at this point)...it forces consumers to subsidize a format that most appear to not really be too interested in. Check out Amazon.com for sales numbers, HD-DVD has a nice head-start.
I also think Nintendo is stealing a bit of Sony's thunder with the Wii. Alot of folks are happy with the 360 and are picking up the Wii as a suplemental console instead of splurging on the PS3. It's trully weird to walk into Best Buy et all and see PS3's sitting on their pallets for hours without anyone batting so much as an eye at them, and it being next to impossible to locate a Wii for retail price. The line I was in over the weekend (still didnt get my Wii) was primarily there for Wii, there were PS3's left over after the initial rush at opening, but Wii's were gone in minutes. Perhaps the tides have turned to the little guys this round.....we shall see.
Cliffs : Get HD-DVD now, if Blu-Ray beats it out it will take a few years to do so, at that point PS3 will be widely available and cheaper. Studios will go with whichever format will get them sales, alliances and friendships be damned.