I thought at first that the MC help files implied that batch normalizing tracks is possible ... here's the relevant excerpt:
Transforms (Alter a Selection)
1. Make a selection (select a portion or select all using Edit > Select All).
2. Choose transform from the Transform menu.
3. Select one of the effects from the Available Transforms list below.
AVAILABLE TRANSFORMS
Adjust Volume
Silence
Normalize
Dynamic Boost
Fade
Stereo Mixing
Reverb
Equalize
However, I guess the help file is actually referring only to the media editor (since the Transform menu is only available in the Editor, and not in the normal MC interface), and when the help file says "select all" it just means "select the entire track" and not "Select all the tracks you want." So the help file should really indicate more clearly that all of the options above are only for use within the Media Editor (found in Tools -> Advanced Tools) and that batching multiple files with these options is not currently possible.
But it does seem like "Normalize before converting" should be an one of the standard MC encoding options, since Normalization is an option when encoding from a rip.... And I don't know why that's not an option, but I'd guess that it's a limitation of the encoder being used (and not MC specifically). But if normalizing is possible when ripping/encoding in MC then why wouldn't it be possible when re-encoding -- wouldn't it be the same encoders being used in either case, and thus the same options should be available? I'm no tech expert, though, and I don't really know anything about the specs on that sort of thing.
Of course, there are strong arguments for why normalization is not a good idea anyway (a band may have specifically made one track on their album quieter than another, but Normalizing will destroy this balance), so many say the MC Analyze Audio feature (found in Tools -> Advanced Tools) should be used instead so that the file's integrity is not altered. The one problem with Analyze Audio being that if you play the file outside of MC the adjustments will not be heard, since they're not saved directly to the file...
But I think the Analyze Audio settings can be kept when burning a CD with the tracks from MC, and -- don't quote me on this -- but don't the Analyze Audio settings also now carry over to the the settings for the track on iPod? If those cases are true, then Analyze Audio is safer than Normalize anyway, since it doesn't permanently alter the file. But for cases where you're sure that you want to permanently normalize a bunch of tracks, being able to batch normalize while re-encoding would be very useful, I agree....
(Note: I'm using MC 11.1, so the above comments may not be completely accurate for MC 10. However, I believe that in the case of this question, the options and navigation are primarily the same between the versions.)
Outside of MC, there are programs out there that can batch normalize MP3 files -- there are even quite a few standalone MP3 Normalizer programs that do this specifically... Many of them cost $$ though, and I haven't tested them, so I can't make a recommendation.