throwing out studio names is silly at this point...
How many titles did Universal release in February/March? How many does Fox/MGM plan to release in April? Also, Warner is definitely leaning HD DVD at the moment (not because they necessarily want to). Point is, things are fluid and throwing out names doesn't matter as much as Sony/Playstation fans are making it out to.
you can't buy half the movies out there on either format, but the truth is, you can buy a ton of movies on BOTH formats right now... consumers see a ton of movies on both formats, with plenty of exclusive stuff on each...
taking engadgethd's count (which is undercounting HD DVD titles):
HD DVD 168 vs Blu-ray 197
Somehow, that 90% studio support vs. 40% studio support doesn't seem to hold up by the number of released titles, and with Warner having trouble with interactive stuff on Blu-ray, this is likely to last a while longer.
Looking at the studio breakdown, you've basically got 6/11 supporting HD DVD, and 9/11 supporting Blu-ray. Blu-ray has an advantage by 3 studios, but as long as the number or releases remain somewhat close, the difference isn't a big deal. Now, if a year from now you have 900 titles on Blu-ray and only 400 on HD DVD, yeah that would be a major blow, but both sides have a ton of stuff coming out.
HD DVD:
Warner
New Line
Paramount
Dreamworks SKG
Universal
Weinstein Co.
Blu-ray:
Warner
New Line
Paramount
Dreamworks SKG
Sony
Fox
Disney
MGM
Lion's Gate
What this means in the end is that both formats are here to stay. Both are far to entrenched to disappear, and most of the movies out there will eventually be on both formats due to studio neutrality. Warner, HBO and Paramount were just the beginning. Soon Dreamworks and New Line will join, and although Universal, Disney, Fox, MGM, and Sony are gonna hold out for quite a while, the rising number of installed base will probably force them to go neutral a few years from now. Weinstein Co. and Lion's Gate, as independents, have little reason to stay neutral as they'll probably want to maximize their profits sooner.